[{
"uri": "WOS:000344052800018",
"title": "The cause of solar dimming and brightening at the Earth's surface during the last half century: Evidence from measurements of sunshine duration",
"abstract": "Analysis of the Angstrom-Prescott relationship between normalized values of global radiation and sunshine duration measured during the last 50 years made at five sites with a wide range of climate and aerosol emissions showed few significant differences in atmospheric transmissivity under clear or cloud-covered skies between years when global dimming occurred and years when global brightening was measured, nor in most cases were there any significant changes in the parameters or in their relationships to annual rates of fossil fuel combustion in the surrounding 1 degrees cells. It is concluded that at the sites studied changes in cloud cover rather than anthropogenic aerosols emissions played the major role in determining solar dimming and brightening during the last half century and that there are reasons to suppose that these findings may have wider relevance.",
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES",
"affiliations": [
"Agr Res Org, Volcani Ctr, Inst Soil Water & Environm Sci, Dept Environm Phys & Irrigat, IL-50250 Bet Dagan, Israel"
],
"countries": [
"Israel"
],
"keywords": [
"CLOUDINESS",
"AEROSOL"
],
"subjects": [
"Meteorology & Atmospheric Sciences"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000344053400018",
"title": "The formation of the recent cooling in the eastern tropical Pacific Ocean and the associated climate impacts: A competition of global warming, IPO, and AMO",
"abstract": "The cooling trend in the eastern tropical Pacific sea surface temperature (SST) during 1979-2008 is examined by using a wide variety of data sets for the ocean and atmosphere. The results show that the cooling trend is statistically significant at the 10% level out of the equator rather than along the equator. Diagnostic analysis indicates that the SST cooling in the eastern tropical Pacific is resulted from a competition of global warming mode, Interdecadal Pacific Oscillation (IPO) mode, and Atlantic Multidecadal Oscillation (AMO) mode. The cooling trend is preliminarily dominated by the phase transition of IPO from positive to negative phases in the year around 1998/1999, which overwhelms the effect of global warming in past three decades. Quantitative estimates based on the average of four different SST data sets indicate that the global warming mode offsets more than half of the cooling effect of IPO mode. The phase transition of AMO during 1990s causes a weak warming trend in the eastern tropical Pacific and partly weakens the cooling, making the trend along the equator less significant. Climate impacts associated with global warming mode, IPO mode, and AMO mode are further examined. The surface air temperature cooling over the eastern tropical Pacific, the easterly wind anomaly along the Pacific equator, the enhanced zonal gradient in sea level pressure over tropical Pacific, and the increased precipitation over the Asian monsoon region during 1979-2008 are dominated by the phase transition of IPO.",
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES",
"affiliations": [
"Chinese Acad Sci, Inst Atmospher Phys, State Key Lab Numer Modeling Atmospher Sci & Geop, Beijing, Peoples R China",
"Univ Chinese Acad Sci, Coll Earth Sci, Beijing, Peoples R China",
"Chinese Acad Sci, Climate Change Res Ctr, Beijing, Peoples R China"
],
"countries": [
"Peoples R China"
],
"keywords": [
"PART II",
"OSCILLATION",
"CIRCULATION",
"ENSO",
"MODULATION",
"PATTERNS",
"PROJECT",
"MODELS",
"DRIVEN",
"ROLES"
],
"subjects": [
"Meteorology & Atmospheric Sciences"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000340609800001",
"title": "The oceanic anthropogenic CO2 sink: Storage, air-sea fluxes, and transports over the industrial era",
"abstract": "This study presents a new estimate of the oceanic anthropogenic CO2 (C-ant) sink over the industrial era (1780 to present), from assimilation of potential temperature, salinity, radiocarbon, and CFC-11 observations in a global steady state ocean circulation inverse model (OCIM). This study differs from previous data-based estimates of the oceanic C-ant sink in that dynamical constraints on ocean circulation are accounted for, and the ocean circulation is explicitly modeled, allowing the calculation of oceanic C-ant storage, air-sea fluxes, and transports in a consistent manner. The resulting uncertainty of the OCIM-estimated C-ant uptake, transport, and storage is significantly smaller than the comparable uncertainty from purely data-based or model-based estimates. The OCIM-estimated oceanic C-ant storage is 160-166 PgC in 2012, and the oceanic C-ant uptake rate averaged over the period 2000-2010 is 2.6 PgC yr(-1) or about 30% of current anthropogenic CO2 emissions. This result implies a residual (primarily terrestrial) C-ant sink of about 1.6 PgC yr(-1) for the same period. The Southern Ocean is the primary conduit for C-ant entering the ocean, taking up about 1.1 PgC yr(-1) in 2012, which represents about 40% of the contemporary oceanic C-ant uptake. It is suggested that the most significant source of remaining uncertainty in the oceanic C-ant sink is due to potential variability in the ocean circulation over the industrial era.",
"publication_year": 2014,
"source": "GLOBAL BIOGEOCHEMICAL CYCLES",
"affiliations": [
"Univ Calif Los Angeles, Dept Atmospher & Ocean Sci, Los Angeles, CA 90095 USA"
],
"countries": [
"USA"
],
"keywords": [
"LAND-USE",
"CARBON",
"MODEL",
"ACIDIFICATION",
"DISTRIBUTIONS",
"PERTURBATION",
"ASSIMILATION",
"VARIABILITY",
"SIMULATION",
"DIFFUSION"
],
"subjects": [
"Environmental Sciences",
"Geosciences, Multidisciplinary",
"Meteorology & Atmospheric Sciences",
"Environmental Sciences & Ecology",
"Geology"
],
"subheadings": [
"Life Sciences & Biomedicine",
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000340402800011",
"title": "Solar radiation management impacts on agriculture in China: A case study in the Geoengineering Model Intercomparison Project (GeoMIP)",
"abstract": "Geoengineering via solar radiation management could affect agricultural productivity due to changes in temperature, precipitation, and solar radiation. To study rice and maize production changes in China, we used results from 10 climate models participating in the Geoengineering Model Intercomparison Project (GeoMIP) G2 scenario to force the Decision Support System for Agrotechnology Transfer (DSSAT) crop model. G2 prescribes an insolation reduction to balance a 1% a(-1) increase in CO2 concentration (1pctCO2) for 50 years. We first evaluated the DSSAT model using 30 years (1978-2007) of daily observed weather records and agriculture practices for 25 major agriculture provinces in China and compared the results to observations of yield. We then created three sets of climate forcing for 42 locations in China for DSSAT from each climate model experiment: (1) 1pctCO2, (2) G2, and (3) G2 with constant CO2 concentration (409 ppm) and compared the resulting agricultural responses. In the DSSAT simulations: (1) Without changing management practices, the combined effect of simulated climate changes due to geoengineering and CO2 fertilization during the last 15 years of solar reduction would change rice production in China by 3.0 +/- 4.0 megaton (Mt) (2.4 +/- 4.0%) as compared with 1pctCO2 and increase Chinese maize production by 18.1 +/- 6.0 Mt (13.9 +/- 5.9%). (2) The termination of geoengineering shows negligible impacts on rice production but a 19.6 Mt (11.9%) reduction of maize production as compared to the last 15 years of geoengineering. (3) The CO2 fertilization effect compensates for the deleterious impacts of changes in temperature, precipitation, and solar radiation due to geoengineering on rice production, increasing rice production by 8.6 Mt. The elevated CO2 concentration enhances maize production in G2, contributing 7.7 Mt (42.4%) to the total increase. Using the DSSAT crop model, virtually all of the climate models agree on the sign of the responses, even though the spread across models is large. This suggests that solar radiation management would have little impact on rice production in China but could increase maize production.",
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES",
"affiliations": [
"Rutgers State Univ, Dept Environm Sci, New Brunswick, NJ 08903 USA",
"Environm Canada, Canadian Ctr Climate Modeling & Anal, Toronto, ON, Canada",
"Univ Victoria, Sch Earth & Ocean Sci, Victoria, BC, Canada",
"Beijing Normal Univ, Coll Global Change & Earth Sci, State Key Lab Earth Surface Processes & Resource, Beijing 100875, Peoples R China",
"Met Off Hadley Ctr, Exeter, Devon, England",
"Pacific NW Natl Lab, Atmospher Sci & Global Change Div, Richland, WA 99352 USA",
"Univ Oslo, Dept Geosci Meteorol & Oceanog, Oslo, Norway",
"Max Planck Inst Meteorol, D-20146 Hamburg, Germany",
"Natl Ctr Atmospher Res, Div Atmospher Chem, Boulder, CO 80307 USA",
"Japan Agcy Marine Earth Sci & Technol, Yokohama, Kanagawa, Japan"
],
"countries": [
"USA",
"Canada",
"Peoples R China",
"England",
"Norway",
"Germany",
"Japan"
],
"keywords": [
"ATMOSPHERIC CARBON-DIOXIDE",
"EARTH SYSTEM MODEL",
"CLIMATE-CHANGE",
"VEGETATION MODEL",
"GISS MODELE",
"RICE",
"FOOD",
"SIMULATIONS",
"NITROGEN",
"BALANCE"
],
"subjects": [
"Meteorology & Atmospheric Sciences"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000340402800031",
"title": "On the seawater temperature dependence of the sea spray aerosol generated by a continuous plunging jet",
"abstract": "Breaking waves on the ocean surface produce bubbles which, upon bursting, deliver seawater constituents into the atmosphere as sea spray aerosol particles. One way of investigating this process in the laboratory is to generate a bubble plume by a continuous plunging jet. We performed a series of laboratory experiments to elucidate the role of seawater temperature on aerosol production from artificial seawater free from organic contamination using a plunging jet. The seawater temperature was varied from -1.3 degrees C to 30.1 degrees C, while the volume of air entrained by the jet, surface bubble size distributions, and size distribution of the aerosol particles produced was monitored. We observed that the volume of air entrained decreased as the seawater temperature was increased. The number of surface bubbles with film radius smaller than 2 mm decreased nonlinearly with seawater temperature. This decrease was coincident with a substantial reduction in particle production. The number concentrations of particles with dry diameter less than similar to 1 mu m decreased substantially as the seawater temperature was increased from -1.3 degrees C to similar to 9 degrees C. With further increase in seawater temperature (up to 30 degrees C), a small increase in the number concentration of larger particles (dry diameter >similar to 0.3 mu m) was observed. Based on these observations, we infer that as seawater temperature increases, the process of bubble fragmentation changes, resulting in decreased air entrainment by the plunging jet, as well as the number of bubbles with film radius smaller than 2 mm. This again results in decreased particle production with increasing seawater temperature.",
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES",
"affiliations": [
"Stockholm Univ, Dept Appl Environm Sci ITM, S-10691 Stockholm, Sweden",
"Univ Copenhagen, Dept Chem, DK-2100 Copenhagen, Denmark",
"Univ Aarhus, Dept Chem, Aarhus, Denmark"
],
"countries": [
"Sweden",
"Denmark"
],
"keywords": [
"BREAKING WAVES",
"GAS ENTRAINMENT",
"SIZE DISTRIBUTIONS",
"BUBBLE ENTRAINMENT",
"ENERGY-DISSIPATION",
"WATER TEMPERATURE",
"OCEANIC WHITECAPS",
"AIR-ENTRAINMENT",
"SIMULATION TANK",
"SURFACE-TENSION"
],
"subjects": [
"Meteorology & Atmospheric Sciences"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000340247000027",
"title": "Radiative forcing of organic aerosol in the atmosphere and on snow: Effects of SOA and brown carbon",
"abstract": "Organic aerosols (OA) play an important role in climate change. However, very few calculations of global OA radiative forcing include secondary organic aerosol (SOA) or the light-absorbing part of OA (brown carbon). Here we use a global model to assess the radiative forcing associated with the change in primary organic aerosol (POA) and SOA between present-day and preindustrial conditions in both the atmosphere and the land snow/sea ice. Anthropogenic emissions are shown to substantially influence the SOA formation rate, causing it to increase by 29 Tg/yr (93%) since preindustrial times. We examine the effects of varying the refractive indices, size distributions for POA and SOA, and brown carbon fraction in SOA. The increase of SOA exerts a direct forcing ranging from -0.12 to -0.31W m(-2) and a first indirect forcing in warm-phase clouds ranging from -0.22 to -0.29W m(-2), with the range due to different assumed SOA size distributions and refractive indices. The increase of POA since preindustrial times causes a direct forcing varying from -0.06 to -0.11W m(-2), when strongly and weakly absorbing refractive indices for brown carbon are used. The change in the total OA exerts a direct forcing ranging from -0.14 to -0.40W m(-2). The atmospheric absorption from brown carbon ranges from +0.22 to +0.57W m(-2), which corresponds to 27%similar to 70% of the black carbon (BC) absorption predicted in the model. The radiative forcing of OA deposited in land snow and sea ice ranges from +0.0011 to +0.0031W m(-2) or as large as 24% of the forcing caused by BC in snow and ice simulated by the model.",
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES",
"affiliations": [
"Univ Michigan, Dept Atmospher Ocean & Space Sci, Ann Arbor, MI 48109 USA",
"Univ Calif San Diego, Scripps Inst Oceanog, San Diego, CA 92103 USA"
],
"countries": [
"USA"
],
"keywords": [
"LIGHT-ABSORPTION",
"BLACK CARBON",
"SPECTRAL DEPENDENCE",
"OPTICAL-PROPERTIES",
"REFRACTIVE-INDEX",
"GLYOXAL UPTAKE",
"GLOBAL-MODEL",
"CLIMATE",
"PHOTOOXIDATION",
"PREINDUSTRIAL"
],
"subjects": [
"Meteorology & Atmospheric Sciences"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000340247000023",
"title": "Process-based analysis of climate model ENSO simulations: Intermodel consistency and compensating errors",
"abstract": "Systematic and compensating errors can lead to degraded predictive skill in climate models. Such errors may be identified by comparing different models in an analysis of individual physical processes. We examine model simulations of El Nino-Southern Oscillation (ENSO) in five Coupled Model Intercomparison Project (CMIP) models, using transfer functions to analyze nine processes critical to ENSO's dynamics. The input and output of these processes are identified and analyzed, some of which are motivated by the recharge oscillator theory. Several errors and compensating errors are identified. The east-west slope of the equatorial thermocline is found to respond to the central equatorial Pacific zonal wind stress as a damped driven harmonic oscillator in all models. This result is shown to be inconsistent with two different formulations of the recharge oscillator. East Pacific sea surface temperature (SST) responds consistently to changes in the thermocline depth in the eastern Pacific in the five CMIP models examined here. However, at time scales greater than 2 years, this consistent model response disagrees with observations, showing that the SST leads thermocline depth at long time scales. Compensating errors are present in the response of meridional transport of water away from the equator to SST: two different models show different response of the transport to off-equatorial wind curl and wind curl response to East Pacific SST. However, these two models show the same response of meridional transport to East Pacific SST. Identification of errors in specific physical processes can hopefully lead to model improvement by focusing model development efforts on these processes.",
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES",
"affiliations": [
"MIT, Dept Earth Atmospher & Planetary Sci, Cambridge, MA 02139 USA",
"Harvard Univ, Dept Earth & Planetary Sci, Cambridge, MA 02138 USA",
"Harvard Univ, Sch Engn & Appl Sci, Cambridge, MA 02138 USA",
"CALTECH, Dept Control & Dynam Syst, Pasadena, CA 91125 USA"
],
"countries": [
"USA"
],
"keywords": [
"ATMOSPHERE FEEDBACKS",
"OCEAN",
"VARIABILITY",
"OSCILLATOR"
],
"subjects": [
"Meteorology & Atmospheric Sciences"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000340247000010",
"title": "The future of Antarctica's surface winds simulated by a high-resolution global climate model: 2. Drivers of 21st century changes",
"abstract": "Antarctica's katabatic winds are among the strongest near-surface winds on Earth, and among the most consistent ones. As these winds are primarily due to the strong surface cooling, greenhouse warming of the surface may act to reduce the strength of these winds as well as their consistency. Here we use the atmospheric component of the global climate model EC-Earth in prescribed sea surface temperature (SST) simulations of the present day (2002-2006) and future (2094-2098) climates, using two model resolutions: (1) T159L62 (similar to 100 km, 62 vertical levels), and (2) T799L91 (similar to 20 km, 91 vertical levels) to investigate changes in Antarctica's surface winds and the reasons thereof. Circumpolar westerlies over the Southern Ocean strengthen and shift poleward because of the deepening of the circumpolar trough and the associated increase in Southern Annular Mode (SAM), especially in high resolution, causing weaker coastal easterlies. Generally, surface wind speeds over the Antarctica mainland exhibit a small decrease. According to the simulations, the temperature deficit (or inversion strength) and associated katabatic forcing exhibit only minor changes over the continent. Changes in the surface winds over Antarctica's slopes can thus be attributed mainly to changes in the synoptic forcing (large-scale pressure gradient). Hence, with modeled 21st century changes in the katabatic forcing being small, changes in zonal and meridional surface winds in and around Antarctica are largely decoupled from those over the Southern Ocean and are governed by changes in synoptic forcing and large-scale pressure gradients. As a result, these changes are largely independent on model resolution.",
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES",
"affiliations": [
"Royal Netherlands Meteorol Inst KNMI, De Bilt, Netherlands"
],
"countries": [
"Netherlands"
],
"keywords": [
"MESOSCALE METEOROLOGICAL CONDITIONS",
"DRONNING MAUD LAND",
"SNOWDRIFT SUBLIMATION",
"KATABATIC WINDS",
"ENERGY BALANCE",
"POLAR-REGIONS",
"BLUE ICE",
"SUMMER"
],
"subjects": [
"Meteorology & Atmospheric Sciences"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000340247000009",
"title": "The future of Antarctica's surface winds simulated by a high-resolution global climate model: 1. Model description and validation",
"abstract": "One of the key components of Antarctica's harsh climate is its renowned katabatic winds, which are among the fiercest surface winds on Earth. Caused primarily by strong surface cooling over the sloping ice surface, these semipermanent winds result primarily from the strong surface temperature inversion and associated temperature deficit between the surface layer and the free atmosphere aloft. Katabatic winds exert a strong effect on the mass budget of the Antarctic ice sheet by affecting snowdrift (sublimation) and by (partially) regulating the net atmospheric moisture transports toward the Antarctic. It has been suggested that greenhouse warming may lead to reduced surface cooling and weakened katabatic winds. This is tested by using a global climate model (EC-Earth) in prescribed sea surface temperature simulations of the present-day (2002-2006) and future (2094-2098) climates. Because simulated topographically induced katabatic winds are likely to depend on the model grid, we employ two model resolutions: (1) T159L62 (similar to 100 km, 62 vertical levels) and (2) T799L91 (similar to 20 km, 91 vertical levels). It is shown here that present-day surface winds over Antarctica in high resolution are generally stronger than in low resolution, especially in the escarpment region with its steep orography. Simulated surface winds are generally underestimated with respect to observations, in particular the strongest winds (occurring over steep slopes), and especially in low resolution. The seasonal cycle in surface winds is simulated fairly accurately. Surface temperatures are also relatively well simulated (when corrected for elevation differences), especially in high resolution.",
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES",
"affiliations": [
"Royal Netherlands Meteorol Inst, NL-3730 AE De Bilt, Netherlands"
],
"countries": [
"Netherlands"
],
"keywords": [
"SNOWDRIFT SUBLIMATION",
"KATABATIC WINDS",
"BALANCE",
"EARTH",
"LAND",
"FLOW"
],
"subjects": [
"Meteorology & Atmospheric Sciences"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000341994000003",
"title": "Attribution of snowmelt onset in Northern Canada",
"abstract": "In the region of Earth most sensitive to climate change, spring snowmelt serves as a measurable indicator of climate change and plays a strong role in the feedbacks that amplify Arctic warming. We characterize the melt season and attribute melt onset in a region of northern Canada during the spring snowmelt season from 2003 to 2011. Melt onset dates are obtained from Advanced Microwave Scanning Radiometer for the Earth Observing System retrievals. Energy balance and meteorological fields are obtained from NASA's Modern Era Retrospective Analysis for Research and Applications product. Analysis of three distinct subregions demonstrates that typical values of energy balance terms vary across the region and have different roles in melt attribution. Melt is controlled more by advective energy farther southwest where melt onset begins sooner, compared to higher levels of radiative energy over the tundra. This study demonstrates that a relatively small region can exhibit large differences in controls on spring snowmelt both within the region and interannually, and these differences can be understood in the context of factors ranging from the large-scale synoptic pattern to land cover and the local energy balance. Being able to attribute melt onset to those drivers that are changing as the high latitudes warm as opposed to those that do not (i.e., insolation) allows better long-term prediction of melt season dynamics and the climatological processes influenced by snow cover and its feedbacks.",
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES",
"affiliations": [
"Rutgers State Univ, Dept Geog, Piscataway, NJ 08854 USA",
"Univ Georgia, Dept Geog, Climatol Res Lab, Athens, GA 30602 USA"
],
"countries": [
"USA"
],
"keywords": [
"SURFACE RADIATIVE FLUXES",
"COVER VARIABILITY",
"LONGWAVE RADIATION",
"CLIMATE-CHANGE",
"MELT",
"ENERGY",
"TEMPERATURE",
"IMPACT",
"BUDGET",
"HEAT"
],
"subjects": [
"Meteorology & Atmospheric Sciences"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000337974500038",
"title": "Global emissions of terpenoid VOCs from terrestrial vegetation in the last millennium",
"abstract": "We investigated the millennial variability (1000 A.D.-2000 A.D.) of global biogenic volatile organic compound (BVOC) emissions by using two independent numerical models: The Model of Emissions of Gases and Aerosols from Nature (MEGAN), for isoprene, monoterpene, and sesquiterpene, and Lund-Potsdam-Jena-General Ecosystem Simulator (LPJ-GUESS), for isoprene and monoterpenes. We found the millennial trends of global isoprene emissions to be mostly affected by land cover and atmospheric carbon dioxide changes, whereas monoterpene and sesquiterpene emission trends were dominated by temperature change. Isoprene emissions declined substantially in regions with large and rapid land cover change. In addition, isoprene emission sensitivity to drought proved to have significant short-term global effects. By the end of the past millennium MEGAN isoprene emissions were 634 TgC yr-1 (13% and 19% less than during 1750-1850 and 1000-1200, respectively), and LPJ-GUESS emissions were 323 TgC yr-1(15% and 20% less than during 1750-1850 and 1000-1200, respectively). Monoterpene emissions were 89 TgC yr-1(10% and 6% higher than during 1750-1850 and 1000-1200, respectively) in MEGAN, and 24 TgC yr-1 (2% higher and 5% less than during 1750-1850 and 1000-1200, respectively) in LPJ-GUESS. MEGAN sesquiterpene emissions were 36 TgC yr-1(10% and 4% higher than during 1750-1850 and 1000-1200, respectively). Although both models capture similar emission trends, the magnitude of the emissions are different. This highlights the importance of building better constraints on VOC emissions from terrestrial vegetation.",
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES",
"affiliations": [
"Stockholm Univ, Dept Appl Environm Sci, S-10691 Stockholm, Sweden",
"Stockholm Univ, Bolin Ctr Climate Res, S-10691 Stockholm, Sweden",
"Univ Helsinki, Dept Phys, Helsinki, Finland",
"Linkoping Univ, NSC, Linkoping, Sweden",
"Inst Coastal Res, Geesthacht, Germany",
"Stockholm Univ, Dept Meteorol, S-10691 Stockholm, Sweden",
"Ecole Polytech Fed Lausanne, Inst Environm Engn, Lausanne, Switzerland",
"PNNL, Atmospher Sci & Global Change Div, Richland, WA USA",
"Karlsruhe Inst Technol, Inst Meteorol & Climate Res, Garmisch Partenkirchen, Germany"
],
"countries": [
"Sweden",
"Finland",
"Germany",
"Switzerland",
"USA"
],
"keywords": [
"ORGANIC-COMPOUND EMISSIONS",
"ISOPRENE EMISSION",
"LAND-USE",
"MONOTERPENE EMISSIONS",
"CO2 CONCENTRATION",
"ATMOSPHERIC CO2",
"CARBON-CYCLE",
"CLIMATE",
"AEROSOL",
"MODEL"
],
"subjects": [
"Meteorology & Atmospheric Sciences"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000337974500025",
"title": "Proxy evidence for China's monsoon precipitation response to volcanic aerosols over the past seven centuries",
"abstract": "The effect of volcanic aerosols on China's monsoon precipitation over the past 700years has been studied using two independently compiled histories of volcanism combined with the Monsoon Asia Drought Atlas. For both reconstructions, four categories of eruptions are distinguished based on the character of their Northern Hemisphere (NH) injection; then Superposed Epoch Analysis (SEA) with a 10,000 Monte Carlo resampling procedure is undertaken for each category and also each individual grid. Results show a statistically significant (at 90% confidence level) drying trend over mainland China from year 1 to year 4 after the eruptions, and the more sulfate aerosol that is injected into the NH stratosphere, the more severe this drying trend. In comparison, a minor wetting trend is observed in the years following Southern Hemisphere-only injections. Results from spatial distribution of the SEA show (1) a southward movement of the significant dry areas in eastern China from year 0 to year 2 after volcanic perturbations that are either equal to or double the size of the 1991 Mount Pinatubo eruption (15T sulfate aerosols in NH) and (2) northeast and northwest China experienced substantial droughts in years 2 to 5. These results are in good agreement with a SEA analysis of the Chinese Historical Drought Disaster Index compiled from historical meteorological records. Our findings illustrate the important role stratospheric aerosols have played in altering China's precipitation during the summer monsoon season and can shed new light on the possible effects that stratospheric geoengineering may have on China's precipitation.",
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES",
"affiliations": [
"Zhejiang Univ, Dept Environm Sci, Hangzhou 310003, Zhejiang, Peoples R China",
"Zhejiang Univ, Dept Math, Hangzhou 310003, Zhejiang, Peoples R China"
],
"countries": [
"Peoples R China"
],
"keywords": [
"ASIAN SUMMER MONSOON",
"CLIMATE",
"DROUGHT",
"MILLENNIUM",
"IMPACTS",
"RECONSTRUCTIONS",
"SIMULATION",
"ERUPTIONS",
"MODEL"
],
"subjects": [
"Meteorology & Atmospheric Sciences"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000337766600020",
"title": "Low-cloud optical depth feedback in climate models",
"abstract": "The relationship between low-level cloud optical depth and atmospheric and surface air temperature is examined in the control climate of 13 climate models to determine if cloud optical depth-temperature relationships found in observations are replicated in climate models and if climate model behavior found in control climate simulations provides information about the optical depth feedback in climate warming simulations forced by increasing carbon dioxide. A positive relationship between cloud optical depth and cloud temperature exists in all models for low clouds with relatively cold temperatures at middle and high latitudes, whereas a negative relationship exists for warmer low clouds in the tropics and subtropics. This relationship is qualitatively similar to that in an earlier analysis of satellite observations, although modeled regression slopes tend to be too positive and their intermodel spread is large. In the models, the cold cloud response comes from increases in cloud water content with increasing temperature, while the warm cloud response comes from decreases in physical thickness with increasing cloud temperature. The intermodel and interregional spread of low-cloud optical depth feedback in climate warming simulations is well predicted by the corresponding spread in the relationships between optical depth and temperature for the current climate, suggesting that this aspect of cloud feedback may be constrained by observations. Because models have a positive bias relative to observations in the optical depth-temperature relationship, shortwave cloud feedback for climate changes may be more positive than climate models currently simulate.",
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES",
"affiliations": [
"Lawrence Livermore Natl Lab, Program Climate Model Diag & Intercomparison, Livermore, CA USA"
],
"countries": [
"USA"
],
"keywords": [
"LIQUID WATER PATH",
"HADLEY-CENTER",
"TEMPERATURE-DEPENDENCE",
"THICKNESS",
"BUDGET",
"ECMWF",
"GCM"
],
"subjects": [
"Meteorology & Atmospheric Sciences"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000337766600018",
"title": "Temporal solar radiation change at high elevations in Hawai'i",
"abstract": "Trends in downwelling global solar irradiance were evaluated at high-elevation sites on the island of Maui, Hawai'i. Departures from monthly means were assessed for the 6 month Hawaiian wet and dry seasons over the period 1988 to 2012. Linear regression analysis was used to characterize trends in each season. For the dry season (May-October), statistically significant (p <= 0.05) positive trends of 9-18 W m(-2) (3-6%) per decade were found at all four high-elevation stations tested. Wet season trends were not significant, except at the highest-elevation station, which had a significant negative trend. No consistent trends in aerosol concentrations have been observed at high elevations in Hawai'i; therefore, the observed dry season brightening is most likely the result of decreasing cloud cover. Supporting this hypothesis, analysis of 15 years (1997-2012) of high temporal resolution Geostationary Operational Environmental Satellite (GOES) imagery over the Hawaiian Islands showed a statistically significant decrease in leeward cloud cover amounting to 5-11% per decade over the stations. In addition, analysis of Moderate Resolution Imaging Spectroradiometer data were in general agreement with the GOES trends, although statistically significant dry season trends were found at only one of the four stations.",
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES",
"affiliations": [
"Univ Hawaii Manoa, Dept Geog, Honolulu, HI 96822 USA",
"Northrop Grumman Corp, Mclean, VA USA",
"Univ Hawaii Manoa, Dept Nat Resource & Environm Management, Honolulu, HI 96822 USA"
],
"countries": [
"USA"
],
"keywords": [
"HADLEY-CELL",
"CLIMATE",
"VARIABILITY",
"CIRCULATION",
"PACIFIC",
"IMPACTS",
"CHOICE",
"REGION"
],
"subjects": [
"Meteorology & Atmospheric Sciences"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000337766600013",
"title": "Anthropogenic heating of the urban environment due to air conditioning",
"abstract": "This article investigates the effect of air conditioning (AC) systems on air temperature and examines their electricity consumption for a semiarid urban environment. We simulate a 10 day extreme heat period over the Phoenix metropolitan area (U.S.) with the Weather Research and Forecasting model coupled to a multilayer building energy scheme. The performance of the modeling system is evaluated against 10 Arizona Meteorological Network weather stations and one weather station maintained by the National Weather Service for air temperature, wind speed, and wind direction. We show that explicit representation of waste heat from air conditioning systems improved the 2m air temperature correspondence to observations. Waste heat release fromAC systems wasmaximumduring the day, but the mean effect was negligible near the surface. However, during the night, heat emitted from AC systems increased the mean 2m air temperature by more than 1 degrees C for some urban locations. The AC systems modified the thermal stratification of the urban boundary layer, promoting vertical mixing during nighttime hours. The anthropogenic processes examined here (i.e., explicit representation of urban energy consumption processes due to AC systems) require incorporation in futuremeteorological and climate investigations to improve weather and climate predictability. Our results demonstrate that releasing waste heat into the ambient environment exacerbates the nocturnal urban heat island and increases cooling demands.",
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES",
"affiliations": [
"Arizona State Univ, Global Inst Sustainabil, Sch Math & Stat Sci, Tempe, AZ 85004 USA",
"Arizona State Univ, Sch Geog Sci & Urban Planning, Tempe, AZ USA"
],
"countries": [
"USA"
],
"keywords": [
"CANOPY MODEL",
"NUMERICAL-SIMULATION",
"PARAMETERIZATION",
"PHOENIX",
"CLIMATE",
"SUMMER",
"ISLAND",
"TEMPERATURE",
"BUILDINGS",
"IMPACTS"
],
"subjects": [
"Meteorology & Atmospheric Sciences"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000340408000013",
"title": "Northern winter climate change: Assessment of uncertainty in CMIP5 projections related to stratosphere-troposphere coupling",
"abstract": "Future changes in the stratospheric circulation could have an important impact on northern winter tropospheric climate change, given that sea level pressure (SLP) responds not only to tropospheric circulation variations but also to vertically coherent variations in troposphere-stratosphere circulation. Here we assess northern winter stratospheric change and its potential to influence surface climate change in the Coupled Model Intercomparison Project-Phase 5 (CMIP5) multimodel ensemble. In the stratosphere at high latitudes, an easterly change in zonally averaged zonal wind is found for the majority of the CMIP5 models, under the Representative Concentration Pathway 8.5 scenario. Comparable results are also found in the 1% CO2 increase per year projections, indicating that the stratospheric easterly change is common feature in future climate projections. This stratospheric wind change, however, shows a significant spread among the models. By using linear regression, we quantify the impact of tropical upper troposphere warming, polar amplification, and the stratospheric wind change on SLP. We find that the intermodel spread in stratospheric wind change contributes substantially to the intermodel spread in Arctic SLP change. The role of the stratosphere in determining part of the spread in SLP change is supported by the fact that the SLP change lags the stratospheric zonally averaged wind change. Taken together, these findings provide further support for the importance of simulating the coupling between the stratosphere and the troposphere, to narrow the uncertainty in the future projection of tropospheric circulation changes.",
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES",
"affiliations": [
"Max Planck Inst Meteorol, D-20146 Hamburg, Germany",
"Finnish Meteorol Inst, FIN-00101 Helsinki, Finland",
"Univ Oxford, Dept Phys, Oxford, England",
"Univ Exeter, Coll Engn Math & Phys Sci, Exeter, Devon, England",
"Georgia Inst Technol, Sch Earth & Atmospher Sci, Atlanta, GA 30332 USA",
"CNR, Ist Sci Atmosfera & Clima, Rome, Italy",
"Univ Complutense Madrid, Dept Fis Tierra 2, Madrid, Spain",
"Univ Reading, Dept Meteorol, Reading, Berks, England",
"Danish Meteorol Inst, Copenhagen, Denmark",
"CNR, Ist Sci Atmosfera & Clima, Turin, Italy",
"NYU, Courant Inst Math Sci, New York, NY USA",
"Met Off Hadley Ctr, Exeter, Devon, England",
"Univ Calif Davis, Dept Land Air & Water Resources, Davis, CA 95616 USA",
"Natl Ctr Atmospher Res, Boulder, CO 80307 USA",
"Kennesaw State Univ, Dept Biol & Phys, Kennesaw, GA USA",
"CSIRO Marine & Atmospher Res, Aspendale, Vic, Australia",
"NASA, Goddard Inst Space Studies, New York, NY 10025 USA",
"Seoul Natl Univ, Sch Earth & Environm Sci, Seoul, South Korea",
"Japan Agcy Marine Earth Sci & Technol, Yokohama, Kanagawa, Japan",
"Univ Reading, Natl Ctr Atmospher Sci, Reading, Berks, England"
],
"countries": [
"Germany",
"Finland",
"England",
"USA",
"Italy",
"Spain",
"Denmark",
"Australia",
"South Korea",
"Japan"
],
"keywords": [
"CIRCULATION RESPONSE",
"TEMPERATURE RESPONSE",
"OZONE RECOVERY",
"WAVE DRAG",
"PART I",
"VARIABILITY",
"ATLANTIC",
"21ST-CENTURY",
"TRENDS",
"IMPACT"
],
"subjects": [
"Meteorology & Atmospheric Sciences"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000337632500015",
"title": "Trends in Southern Hemisphere wind-driven circulation in CMIP5 models over the 21st century: Ozone recovery versus greenhouse forcing",
"abstract": "During the late 20th century, Antarctic ozone depletion and increasing greenhouse gases (GHGs) conspired to generate conspicuous atmospheric circulation trends in the Southern Hemisphere (SH), contributing to a poleward intensification of the oceanic supergyre circulation. Forcing of Antarctic ozone depletion dominated the observed trends during the depletion period (1979-2005), but Antarctic ozone is projected to recover by the middle of the 21st century. The recovery provides a mechanism for offsetting the impact from increasing GHG emissions. To what extent will the recovery of ozone mitigate SH atmosphere and ocean circulation trends expected from increasing GHGs? We examine climate model output from the Representative Concentration Pathway 4.5 and 8.5 (RCP4.5 and RCP8.5, respectively) emission scenario experiments, submitted to the Coupled Model Intercomparison Project phase 5. Both scenarios are subject to the effect of ozone recovery. We show that during the recovery period (2006-2045), there is little poleward shift of the supergyre circulation under either RCP scenario in austral summer, due to the dominance of ozone recovery. Further, under RCP8.5 the trend in winter, a season in which ozone recovery has little impact, is greater (more poleward) than in summer, opposite to the seasonality of trends during the depletion period. Under RCP4.5, with the contribution from ozone recovery, the summer poleward shift is projected to stabilize into the postrecovery decades, whereas under RCP8.5, the summer poleward shift accelerates in the postrecovery period, presenting vastly different ocean circulation futures.",
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS",
"affiliations": [
"Ocean Univ China, Phys Oceanog Lab, Qingdao, Peoples R China",
"CSIRO Marine & Atmospher Res, Aspendale, Vic, Australia"
],
"countries": [
"Peoples R China",
"Australia"
],
"keywords": [
"IPCC AR4 MODELS",
"CLIMATE-CHANGE",
"ANNULAR MODE",
"SUBTROPICAL PRECIPITATION",
"DEPLETION",
"OCEAN",
"IMPACT",
"WESTERLIES",
"WORLD",
"GYRE"
],
"subjects": [
"Oceanography"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000340415500033",
"title": "Variability of sea-ice in the northern Weddell Sea during the 20th century",
"abstract": "The record of winter fast-ice in the South Orkney Islands, northern Weddell Sea, Antarctica, is over a century long and provides the longest observational record of sea-ice variability in the Southern Hemisphere. Here we present analyses of the series of fast-ice formation and breakout dates from 1903 to 2008. We show that over the satellite era (post-1979), the timing of both final autumn formation and complete spring breakout of fast-ice is representative of the regional sea-ice concentrations (SIC) in the northern Weddell Sea, and associated with atmospheric conditions in the Amundsen Sea region to the west of the Antarctic Peninsula. Variation in the fast-ice breakout date is influenced by the intensity of the westerly/north-westerly winds associated with the Southern Annular Mode (SAM). In contrast, the date of ice formation displays correlations with regional oceanic and sea-ice conditions over the previous 18 months, which indicate a preconditioning during the previous summer and winter, and exhibits variability associated with variation in tropical Pacific sea-surface temperature (i.e., the El Nino-Southern Oscillation, ENSO). A reduction in fast-ice duration at the South Orkney Islands around the 1950s was associated with both later formation and earlier breakout. However, there were marked changes in variability (with periodicities of 3-5, 7-9, and 20 years) in each of the series and in their relationships with ENSO and SAM, indicating the need for caution in interpreting changes in ice conditions based on shorter-term satellite series.",
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS",
"affiliations": [
"British Antarctic Survey, NERC, Cambridge, England",
"Univ E Anglia, Sch Environm Sci, Norwich NR4 7TJ, Norfolk, England",
"Australian Natl Univ, Res Sch Earth Sci, Canberra, ACT, Australia"
],
"countries": [
"England",
"Australia"
],
"keywords": [
"SOUTHERN-HEMISPHERE CLIMATE",
"WHALING RECORDS",
"ANNULAR MODE",
"PART II",
"EXTENT",
"ECOSYSTEM",
"TRENDS",
"SAM",
"TEMPERATURE",
"ATMOSPHERE"
],
"subjects": [
"Oceanography"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000334908300014",
"title": "Comment on \"The added value to global model projections of climate change by dynamical downscaling: A case study over the continental U. S. using the GISS-ModelE2 and WRF models\" by Racherla et al.",
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES",
"affiliations": [
"Univ Quebec Montreal, Dept Earth & Atmospher Sci, ESCER Ctr, Montreal, PQ, Canada"
],
"countries": [
"Canada"
],
"keywords": "TEMPERATURE TRENDS",
"subjects": [
"Meteorology & Atmospheric Sciences"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000334908300031",
"title": "The climatic effects of modifying cirrus clouds in a climate engineering framework",
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES",
"affiliations": [
"Univ Oslo, Dept Geosci, Oslo, Norway",
"Yale Univ, Dept Geol & Geophys, New Haven, CT USA",
"Iceland Meteorol Off, Reykjavik, Iceland"
],
"countries": [
"Norway",
"USA",
"Iceland"
],
"keywords": [
"COMMUNITY ATMOSPHERE MODEL",
"MICROPHYSICS SCHEME",
"ALBEDO-ENHANCEMENT",
"PART I",
"ICE",
"SUMMER",
"PRECIPITATION",
"PARTICLES",
"CONTRAILS",
"AEROSOLS"
],
"subjects": [
"Meteorology & Atmospheric Sciences"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000334908300018",
"title": "Postlaunch calibration and bias characterization of AMSU-A upper air sounding channels using GPS RO Data",
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES",
"affiliations": [
"Nanjing Univ Informat & Sci & Technol, Ctr Data Assimilat Res & Applicat, Nanjing, Jiangsu, Peoples R China",
"Florida State Univ, Dept Earth Ocean & Atmospher Sci, Tallahassee, FL 32306 USA"
],
"countries": [
"Peoples R China",
"USA"
],
"keywords": [
"RADIO OCCULTATION DATA",
"TROPOSPHERIC TEMPERATURE",
"EARTHS ATMOSPHERE",
"DATA ASSIMILATION",
"MSU CHANNEL-2",
"UNIT",
"CLIMATE",
"SYSTEM",
"CHAMP",
"CONSTRUCTION"
],
"subjects": [
"Meteorology & Atmospheric Sciences"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000337974500036",
"title": "A new look at methane and nonmethane hydrocarbon emissions from oil and natural gas operations in the Colorado Denver-Julesburg Basin",
"abstract": "Emissions of methane (CH4) from oil and natural gas (O&G) operations in the most densely drilled area of the Denver-Julesburg Basin in Weld County located in northeastern Colorado are estimated for 2days in May 2012 using aircraft-based CH4 observations and planetary boundary layer height and ground-based wind profile measurements. Total top-down CH4 emission estimates are 25.8 +/- 8.4 and 26.2 +/- 10.7 t CH4/h for the 29 and 31 May flights, respectively. Using inventory data, we estimate the total emissions of CH4 from non-O&G gas-related sources at 7.1 +/- 1.7 and 6.3 +/- 1.0 t CH4/h for these 2days. The difference in emissions is attributed to O&G sources in the study region, and their total emission is on average 19.3 +/- 6.9 t/h, close to 3 times higher than an hourly emission estimate based on Environmental Protection Agency's Greenhouse Gas Reporting Program data for 2012. We derive top-down emissions estimates for propane, n-butane, i-pentane, n-pentane, and benzene from our total top-down CH4 emission estimate and the relative hydrocarbon abundances in aircraft-based discrete air samples. Emissions for these five nonmethane hydrocarbons alone total 25.4 +/- 8.2 t/h. Assuming that these emissions are solely originating from O&G-related activities in the study region, our results show that the state inventory for total volatile organic compounds emitted by O&G activities is at least a factor of 2 too low for May 2012. Our top-down emission estimate of benzene emissions from O&G operations is 173 +/- 64 kg/h, or 7 times larger than in the state inventory.",
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES",
"affiliations": [
"Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA",
"NOAA Earth Syst Res Lab, Boulder, CO USA",
"Univ Colorado, Inst Arctic & Alpine Res, Boulder, CO 80309 USA",
"Univ Calif Davis, Dept Land Air & Water Resources, Davis, CA 95616 USA",
"Univ Colorado, Dept Atmospher & Ocean Sci, Boulder, CO 80309 USA"
],
"countries": [
"USA"
],
"keywords": [
"UNITED-STATES",
"CARBON-MONOXIDE",
"GREENHOUSE-GAS",
"TRACER METHODS",
"CATTLE",
"FRONT",
"CALIFORNIA",
"SYSTEMS",
"MANURE",
"SITES"
],
"subjects": [
"Meteorology & Atmospheric Sciences"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000335809100029",
"title": "Roles of transport and chemistry processes in global ozone change on interannual and multidecadal time scales",
"abstract": "This study investigates ozone changes and the individual impacts of transport and chemistry on those changes. We specifically examine (1) variation related to El Nino Southern Oscillation, which is a dominant mode of interannual variation of tropospheric ozone, and (2) long-term change between the 2000s and 2100s. During El Nino, the simulated ozone shows an increase (1 ppbv/K) over Indonesia, a decrease (2-10 ppbv/K) over the eastern Pacific in the tropical troposphere, and an increase (50 ppbv/K) over the eastern Pacific in the midlatitude lower stratosphere. These variations fundamentally agree with those observed by Microwave Limb Sounder/Tropospheric Emission Spectrometer instruments. The model demonstrates that tropospheric chemistry has a strong impact on the variation over the eastern Pacific in the tropical lower troposphere and that transport dominates the variation in the midlatitude lower stratosphere. Between the 2000s and 2100s, the model predicts an increase in the global burden of stratospheric ozone (0.24%/decade) and a decrease in the global burden of tropospheric ozone (0.82%/decade). The increase in the stratospheric burden is controlled by stratospheric chemistry. Tropospheric chemistry reduces the tropospheric burden by 1.07%/decade. However, transport (i.e., stratosphere-troposphere exchange and tropospheric circulation) causes an increase in the burden (0.25%/decade). Additionally, we test the sensitivity of ozone changes to increased horizontal resolution of the representation of atmospheric circulation and advection apart from any aspects of the nonlinearity of chemistry sensitivity to horizontal resolution. No marked difference is found in medium-resolution or high-resolution simulations, suggesting that the increased horizontal resolution of transport has a minor impact.",
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES",
"affiliations": [
"Nagoya Univ, Grad Sch Environm Studies, Nagoya, Aichi 4648601, Japan"
],
"countries": [
"Japan"
],
"keywords": [
"STRATOSPHERE-TROPOSPHERE EXCHANGE",
"GENERAL-CIRCULATION MODEL",
"1997-1998 EL-NINO",
"CLIMATE MODEL",
"ATMOSPHERIC CHEMISTRY",
"SATELLITE MEASUREMENTS",
"IMPACT",
"SIMULATION",
"ENSO",
"MIDLATITUDES"
],
"subjects": [
"Meteorology & Atmospheric Sciences"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000332995300015",
"title": "Do sophisticated parameterizations of aerosol-cloud interactions in CMIP5 models improve the representation of recent observed temperature trends?",
"abstract": "Model output from the Coupled Model Intercomparison Project phase 5 (CMIP5) archive was compared with the observed latitudinal distribution of surface temperature trends between the years 1965 and 2004. By comparing model simulations that only consider changes in greenhouse gas forcing (GHG) with simulations that also consider the time evolution of anthropogenic aerosol emissions (GHGAERO), the influence of aerosol forcing on modeled surface temperature trends, and the dependence of the forcing on the model representation of aerosols and aerosol indirect effects, was evaluated. One group of models include sophisticated parameterizations of aerosol activation into cloud droplets; viz., the cloud droplet number concentration (CDNC) is a function of the modeled supersaturation as well as the aerosol concentration. In these models, the temperature trend bias was reduced in GHGAERO compared to GHG in more regions than in the other models. The ratio between high- and low-latitude warming also improved compared to observations. In a second group of models, the CDNC is diagnosed using an empirical relationship between the CDNC and the aerosol concentration. In this group, the temperature trend bias was reduced in more regions than in the model group where no aerosol indirect effects are considered. No clear difference could be found between models that include an explicit aerosol module and the ones that utilize prescribed aerosol. There was also no clear difference between models that include aerosol effects on the precipitation formation rate and the ones that do not. The results indicate that the best representation of recent observed surface temperature trends is obtained if the modeled CDNC is a function of both the aerosol concentration and the supersaturation.",
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES",
"affiliations": [
"Stockholm Univ, Dept Meteorol, S-10691 Stockholm, Sweden",
"Stockholm Univ, Bolin Ctr Climate Res, S-10691 Stockholm, Sweden"
],
"countries": [
"Sweden"
],
"keywords": [
"CLIMATE-CHANGE PROJECTIONS",
"CIRCULATION"
],
"subjects": [
"Meteorology & Atmospheric Sciences"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000332995300006",
"title": "Arctic sea ice and atmospheric circulation under the GeoMIP G1 scenario",
"abstract": [
"We analyze simulated sea ice changes in eight different Earth System Models that have conducted experiment G1 of the Geoengineering Model Intercomparison Project (GeoMIP). The simulated response of balancing abrupt quadrupling of CO2 (abrupt4xCO2) with reduced shortwave radiation successfully moderates annually averaged Arctic temperature rise to about 1 degrees C, with modest changes in seasonal sea ice cycle compared with the preindustrial control simulations (piControl). Changes in summer and autumn sea ice extent are spatially correlated with temperature patterns but much less in winter and spring seasons. However, there are changes of 20% in sea ice concentration in all seasons, and these will induce changes in atmospheric circulation patterns. In summer and autumn, the models consistently simulate less sea ice relative to preindustrial simulations in the Beaufort, Chukchi, East Siberian, and Laptev Seas, and some models show increased sea ice in the Barents/Kara Seas region. Sea ice extent increases in the Greenland Sea, particularly in winter and spring and is to some extent associated with changed sea ice drift. Decreased sea ice cover in winter and spring in the Barents Sea is associated with increased cyclonic activity entering this area under G1. In comparison, the abrupt4xCO2 experiment shows almost total sea ice loss in September and strong correlation with regional temperatures in all seasons consistent with open ocean conditions. The tropospheric circulation displays a Pacific North America pattern-like anomaly with negative phase in G1-piControl and positive phase under abrupt4xCO2-piControl.",
"Key Points",
" Analysis of eight ESM focused on Arctic sea ice and feedback Response of Arctic to G1 geoengineering shows clear regional differences Sea ice is far different in detail under G1 than in pre industrial"
],
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES",
"affiliations": [
"Beijing Normal Univ, State Key Lab Earth Surface Proc & Resource Ecol, Coll Global Change & Earth Syst Sci, Beijing 100875, Peoples R China",
"Alfred Wegener Inst Helmholtz Ctr Polar & Marine, Potsdam, Germany",
"Lanzhou Univ, Coll Atmospher Sci, Lanzhou 730000, Peoples R China",
"Univ Oslo, Dept Geosci, Oslo, Norway",
"UPMC, CNRS, IPSL, Lab Meteorol Dynam, Paris, France",
"Pacific NW Natl Lab, Atmospher Sci & Global Change Div, Richland, WA 99352 USA",
"Rutgers State Univ, Dept Environm Sci, New Brunswick, NJ 08903 USA",
"Max Planck Inst Meteorol, D-20146 Hamburg, Germany",
"Norwegian Meteorol Inst, Oslo, Norway",
"Natl Ctr Atmospher Res, Boulder, CO 80307 USA",
"Japan Agcy Marine Earth Sci & Technol, Yokohama, Kanagawa, Japan",
"Danish Meteorol Inst, Danish Climate Ctr, Copenhagen, Denmark"
],
"countries": [
"Peoples R China",
"Germany",
"Norway",
"France",
"USA",
"Japan",
"Denmark"
],
"keywords": [
"FUTURE CLIMATE PROJECTIONS",
"NORTHERN-HEMISPHERE",
"TELECONNECTION PATTERN",
"GEOPOTENTIAL HEIGHT",
"BARENTS SEA",
"IMPACT",
"WINTER",
"VARIABILITY",
"TRACK",
"MODES"
],
"subjects": [
"Meteorology & Atmospheric Sciences"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000334264900040",
"title": "Impact of the Atlanticmeridional overturning circulation on ocean heat storage and transient climate change",
"abstract": [
"We propose here that the Atlantic meridional overturning circulation (AMOC) plays an important role in setting the effective heat capacity of the World Ocean and thus impacts the pace of transient climate change. The depth and strength of AMOC are shown to be strongly correlated with the depth of heat storage across a suite of state-of-the-art general circulation models (GCMs). In those models with a deeper and stronger AMOC, a smaller portion of the heat anomaly remains in the ocean mixed layer, and consequently, the surface temperature response is delayed. Representations of AMOC differ vastly across the GCMs, providing a major source of intermodel spread in the sea surface temperature (SST) response. A two-layer model fit to the GCMs is used to demonstrate that the intermodel spread in SSTs due to variations in the ocean's effective heat capacity is significant but smaller than the spread due to climate feedbacks.",
"Key Points AMOC plays a key role in setting the effective heat capacity of the World Ocean AMOC properties are correlated with depth of heat storage across CMIP5 GCMs Ocean heat storage is a major source of inter-GCM variability in SST response"
],
"publication_year": 2014,
"source": "GEOPHYSICAL RESEARCH LETTERS",
"affiliations": [
"MIT, Dept Earth Atmospher & Planetary Sci, Cambridge, MA 02139 USA"
],
"countries": [
"USA"
],
"keywords": [
"TEMPERATURE",
"SENSITIVITY"
],
"subjects": [
"Geosciences, Multidisciplinary",
"Geology"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000334264900041",
"title": "Astronomically forced variations in western African rainfall ( 21 N-20 S) during the Last Interglacial period",
"abstract": [
"This study documents the long-term evolution of western African precipitation during the Last Interglacial (LIG). We compare geochemical records obtained on nine sediment cores from the western African margin to a transient simulation (130-115ka) performed with an ocean-atmosphere general circulation model and insolation as sole forcing. Good agreement between proxy records and model outputs indicates that long-term changes in western African precipitation largely responded to insolation variations during most of the LIG. After an early LIG dry phase (related to high-latitude iceberg melting or dating uncertainties), boreal summer insolation controlled the intensification of the North African monsoon between 127 and 122ka, perhaps facilitating human migrations out of Africa. Equatorial African rainfall slightly increased throughout the LIG in response to increasing annual insolation. East-west contrasting rainfall evolutions at 10-20 degrees S illustrate the complex southern African response, in contrast to more direct responses of North and equatorial western Africa, to insolation forcing.",
"Key Points",
"Insolation controls changes in western African rainfall during most of the LIG Early LIG meltwater may have delayed the North African monsoon intensification Complex response of southern African rainfall with east-west contrasting trends"
],
"publication_year": 2014,
"source": "GEOPHYSICAL RESEARCH LETTERS",
"affiliations": [
"Univ Bremen, MARUM Ctr Marine Environm Sci, D-28359 Bremen, Germany"
],
"countries": [
"Germany"
],
"keywords": [
"MODERN HUMANS",
"WET PHASES",
"CLIMATE",
"MONSOON",
"ATLANTIC",
"SAHARA",
"MODEL",
"SIMULATIONS",
"VEGETATION",
"INSOLATION"
],
"subjects": [
"Geosciences, Multidisciplinary",
"Geology"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000334534500009",
"title": "A 170 year spring phenology index of plants in eastern China",
"abstract": "Extending phenological records into the past is essential for the understanding of past ecological change and evaluating the effects of climate change on ecosystems. A growing body of historical phenological information is now available for Europe, North America, and Asia. In East Asia, long-term phenological series are still relatively scarce. This study extracted plant phenological observations from old diaries in the period 1834-1962. A spring phenology index (SPI) for the modern period (1963-2009) was defined as the mean flowering time of three shrubs (first flowering of Amygdalus davidiana and Cercis chinensis, 50% of full flowering of Paeonia suffruticosa) according to the data availability. Applying calibrated transfer functions from the modern period to the historical data, we reconstructed a continuous SPI time series across eastern China from 1834 to 2009. In the recent 30 years, the SPI is 2.1-6.3 days earlier than during any other consecutive 30year period before 1970. A moving linear trend analysis shows that the advancing trend of SPI over the past three decades reaches upward of 4.1d/decade, which exceeds all previously observed trends in the past 30year period. In addition, the SPI series correlates significantly with spring (February to April) temperatures in the study area, with an increase in spring temperature of 1 degrees C inducing an earlier SPI by 3.1days. These shifts of SPI provide important information regarding regional vegetation-climate relationships, and they are helpful to assess long term of climate change impacts on biophysical systems and biodiversity.",
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES",
"affiliations": [
"Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing, Peoples R China",
"Univ Chinese Acad Sci, Beijing, Peoples R China",
"Univ Bern, Oeschger Ctr Climate Change Res OCCR, Bern, Switzerland",
"Univ Bern, Inst Geog, Bern, Switzerland"
],
"countries": [
"Peoples R China",
"Switzerland"
],
"keywords": [
"GROWING-SEASON",
"CLIMATE-CHANGE",
"YANGTZE-RIVER",
"TIME-SERIES",
"BUD BURST",
"TEMPERATURE",
"RESPONSES",
"RECONSTRUCTION",
"PATTERNS",
"FINLAND"
],
"subjects": [
"Environmental Sciences",
"Geosciences, Multidisciplinary",
"Environmental Sciences & Ecology",
"Geology"
],
"subheadings": [
"Life Sciences & Biomedicine",
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000333578800056",
"title": "Predictability of the quasi-biennial oscillation and its northern winter teleconnection on seasonal to decadal timescales",
"abstract": [
"The predictability of the quasi-biennial oscillation (QBO) is examined in initialized climate forecasts extending out to lead times of years. We use initialized retrospective predictions made with coupled ocean-atmosphere climate models that have an internally generated QBO. We demonstrate predictability of the QBO extending more than 3 years into the future, well beyond timescales normally associated with internal atmospheric processes. Correlation scores with observational analyses exceed 0.7 at a lead time of 12months. We also examine the variation of predictability with season and QBO phase and find that skill is lowest in winter. An assessment of perfect predictability suggests that higher skill may be achievable through improved initialization and climate modeling of the QBO, although this may depend on the realism of gravity wave source parameterizations in the models. Finally, we show that skilful prediction of the QBO itself does not guarantee predictability of the extratropical winter teleconnection that is important for surface winter climate prediction.",
"Key Points",
" The QBO is skilfully predicted in seasonal-decadal forecast systems Further improvements in predictions of the QBO are possible The QBO winter surface teleconnection is reproduced with mixed success"
],
"publication_year": 2014,
"source": "GEOPHYSICAL RESEARCH LETTERS",
"affiliations": [
"Met Off Hadley Ctr, Exeter, Devon, England",
"Univ Exeter, Dept Math & Comp Sci, Exeter, Devon, England",
"Max Planck Inst Meteorol, D-20146 Hamburg, Germany",
"European Ctr Medium Range Weather Forecasts, Reading RG2 9AX, Berks, England"
],
"countries": [
"England",
"Germany"
],
"keywords": [
"OFFICE UNIFIED MODEL",
"GLOBAL CLIMATE",
"CIRCULATION",
"STRATOSPHERE",
"PREDICTIONS",
"WAVES",
"SKILL",
"REANALYSIS",
"ATMOSPHERE",
"FLUXES"
],
"subjects": [
"Geosciences, Multidisciplinary",
"Geology"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000333578800054",
"title": "Modifications of the quasi-biennial oscillation by a geoengineering perturbation of the stratospheric aerosol layer",
"abstract": [
"This paper examines the impact of geoengineering via stratospheric sulfate aerosol on the quasi-biennial oscillation (QBO) using the NASA Goddard Earth Observing System version 5 Chemistry Climate Model. We performed four 30 year simulations with a continuous injection of sulfur dioxide on the equator at 0 degrees longitude. The four simulations differ by the amount of sulfur dioxide injected (5 Tg/yr and 2.5 Tg/yr) and the altitude of the injection (16km-25km and 22km-25km). We find that such an injection dramatically alters the quasi-biennial oscillation, prolonging the phase of easterly shear with respect to the control simulation. This is caused by the increased aerosol heating and associated warming in the tropical lower stratosphere and higher residual vertical velocity. In the case of maximum perturbation, i.e., highest stratospheric aerosol burden, the lower tropical stratosphere is locked into a permanent westerly QBO phase.",
"Key Points",
" Geoengineering aerosol would prolong the westerly phase of the QBO Large geoengineering stratospheric aerosol injections might interrupt the QBO QBO changes are due to aerosol warming and increased residual vertical velocity"
],
"publication_year": 2014,
"source": "GEOPHYSICAL RESEARCH LETTERS",
"affiliations": [
"Goddard Earth Sci Technol & Res, Greenbelt, MD 20771 USA",
"Johns Hopkins Univ, Dept Earth & Planetary Sci, Baltimore, MD 21218 USA",
"Hebrew Univ Jerusalem, Fredy & Nadine Herrmann Inst Earth Sci, Jerusalem, Israel",
"NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA"
],
"countries": [
"USA",
"Israel"
],
"keywords": [
"PINATUBO ERUPTION",
"OZONE",
"CIRCULATION",
"QBO"
],
"subjects": [
"Geosciences, Multidisciplinary",
"Geology"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000333578800044",
"title": "The implication of radiative forcing and feedback for meridional energy transport",
"abstract": [
"The distributions of radiative forcing and feedback in the Coupled Model Intercomparison Project phase 5 abrupt4xCO2 and Historical experiments are diagnosed, with a focus on their effects on the zonal mean structure of the top-of-the-atmosphere radiation anomalies and implications for the meridional energy transport. It is found that because the greenhouse gas longwave forcing peaks in the low latitudes, it reinforces the equator-to-pole net radiation gradient and accounts for the increase in the poleward energy transport in both hemispheres under global warming. The shortwave forcing by aerosol, ozone, etc. peaks in the Northern Hemisphere and instead implies an interhemispheric energy transport. Although the water vapor feedback also reinforces the equator-to-pole gradient of the net radiation, the temperature and albedo feedback act against it. The feedback tend to offset the zonal mean radiation anomaly caused by the forcing, although the overall feedback effect on the energy transport is rather uncertain, mainly due to the uncertainty in the cloud feedback.",
"Key Points",
" CO2 forcing increases meridional gradient in net radiation Forcing, rather than feedback, accounts for enhanced poleward energy transport Aerosol forcing accounts for an inter-hemispheric transport anomaly"
],
"publication_year": 2014,
"source": "GEOPHYSICAL RESEARCH LETTERS",
"affiliations": [
"McGill Univ, Dept Atmospher & Ocean Sci, Montreal, PQ, Canada"
],
"countries": [
"Canada"
],
"keywords": [
"CLIMATE FEEDBACKS",
"ATMOSPHERIC CO2",
"MODEL",
"RESPONSES",
"SPREAD"
],
"subjects": [
"Geosciences, Multidisciplinary",
"Geology"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000332995300011",
"title": "Evaluation of interpolation techniques for the creation of gridded daily precipitation ( 1 x 1 km2); Cyprus, 1980-2010",
"abstract": [
"High-resolution gridded daily data sets are essential for natural resource management and the analyses of climate changes and their effects. This study aims to evaluate the performance of 15 simple or complex interpolation techniques in reproducing daily precipitation at a resolution of 1km(2) over topographically complex areas. Methods are tested considering two different sets of observation densities and different rainfall amounts. We used rainfall data that were recorded at 74 and 145 observational stations, respectively, spread over the 5760km(2) of the Republic of Cyprus, in the Eastern Mediterranean. Regression analyses utilizing geographical copredictors and neighboring interpolation techniques were evaluated both in isolation and combined. Linear multiple regression (LMR) and geographically weighted regression methods (GWR) were tested. These included a step-wise selection of covariables, as well as inverse distance weighting (IDW), kriging, and 3D-thin plate splines (TPS). The relative rank of the different techniques changes with different station density and rainfall amounts. Our results indicate that TPS performs well for low station density and large-scale events and also when coupled with regression models. It performs poorly for high station density. The opposite is observed when using IDW. Simple IDW performs best for local events, while a combination of step-wise GWR and IDW proves to be the best method for large-scale events and high station density. This study indicates that the use of step-wise regression with a variable set of geographic parameters can improve the interpolation of large-scale events because it facilitates the representation of local climate dynamics.",
"Key Points",
" Interpolation of daily rainfall data using 15 spatial interpolation methods Relative skill of interpolation techniques depends on observation density High and low rainfall events should be treated with different techniques"
],
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES",
"affiliations": [
"Cyprus Inst, Nicosia, Cyprus",
"Cyprus Meteorol Serv, Nicosia, Cyprus"
],
"countries": [
"Cyprus"
],
"keywords": [
"CLIMATE-CHANGE",
"OBJECTIVE ANALYSIS",
"WEATHER GENERATOR",
"CROP GROWTH",
"PART II",
"TEMPERATURE",
"MODEL",
"RAINFALL",
"VALIDATION",
"REGRESSION"
],
"subjects": [
"Meteorology & Atmospheric Sciences"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000333885700038",
"title": "Stratospheric ozone response to sulfate geoengineering: Results from the Geoengineering Model Intercomparison Project (GeoMIP)",
"abstract": "Geoengineering with stratospheric sulfate aerosols has been proposed as a means of temporarily cooling the planet, alleviating some of the side effects of anthropogenic CO2 emissions. However, one of the known side effects of stratospheric injections of sulfate aerosols under present-day conditions is a general decrease in ozone concentrations. Here we present the results from two general circulation models and two coupled chemistry-climate models within the experiments G3 and G4 of the Geoengineering Model Intercomparison Project. On average, the models simulate in G4 an increase in sulfate aerosol surface area density similar to conditions a year after the Mount Pinatubo eruption and a decrease in globally averaged ozone by 1.1-2.1 DU (Dobson unit, 1 DU = 0.001 atm cm) during the central decade of the experiment (2040-2049). Enhanced heterogeneous chemistry on sulfate aerosols leads to an ozone increase in low and middle latitudes, whereas enhanced heterogeneous reactions in polar regions and increased tropical upwelling lead to a reduction of stratospheric ozone. The increase in UV-B radiation at the surface due to ozone depletion is offset by the screening due to the aerosols in the tropics and midlatitudes, while in polar regions the UV-B radiation is increased by 5% on average, with 12% peak increases during springtime. The contribution of ozone changes to the tropopause radiative forcing during 2040-2049 is found to be less than -0.1 W m(-2). After 2050, because of decreasing ClOx concentrations, the suppression of the NOx cycle becomes more important than destruction of ozone by ClOx, causing an increase in total stratospheric ozone.",
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES",
"affiliations": [
"Univ Aquila, Dept Phys & Chem Sci, I-67100 Laquila, Italy",
"Univ Aquila, Ctr Excellence CETEMPS, I-67100 Laquila, Italy",
"Johns Hopkins Univ, GESTAR, NASA GSFC, Greenbelt, MD USA",
"Pacific NW Natl Lab, Atmospher Sci & Global Change Div, Richland, WA 99352 USA",
"Rutgers State Univ, Dept Environm Sci, New Brunswick, NJ 08903 USA",
"Japan Agcy Marine Earth Sci & Technol, Yokohama, Kanagawa, Japan",
"ENEA, Ente Nuove Tecnol Energia & Ambiente, Rome, Italy",
"Natl Ctr Atmospher Res, Boulder, CO 80307 USA"
],
"countries": [
"Italy",
"USA",
"Japan"
],
"keywords": [
"AEROSOL-SIZE DISTRIBUTION",
"MOUNT-PINATUBO",
"ATMOSPHERIC CHEMISTRY",
"VOLCANIC-ERUPTIONS",
"GLOBAL CLIMATOLOGY",
"SOLAR-RADIATION",
"II MEASUREMENTS",
"TROPICAL OZONE",
"IN-SITU",
"IMPACT"
],
"subjects": [
"Meteorology & Atmospheric Sciences"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000333885700023",
"title": "Cirrus cloud susceptibility to the injection of ice nuclei in the upper troposphere",
"abstract": [
"Due to their net warming effect, cirrus clouds play a crucial role in the climate system. A recently proposed climate engineering mechanism (CEM) intends to reduce high cloud cover by seeding cirrus clouds with efficient ice nuclei (IN) and therefore cool climate. Here, the susceptibility of cirrus clouds to the injection of ice nuclei in the upper troposphere is investigated in the extended Community Atmospheric Model version 5 (CAM5). Due to large uncertainties associated with the dominant ice nucleation mechanism in cirrus clouds, different control cases were simulated. In addition to pure homogeneous and heterogeneous nucleation, cases with competition between homogeneous and heterogeneous nucleation and different fractions of mineral dust active as IN were considered. Whereas seeding in the pure heterogeneous case leads to a strong warming due to overseeding, an optimal seeding IN concentration of approximately 18 l(-1) was found for the other cases. For the optimal seeding concentration, a reduction in the net cloud forcing (NCF) of up to 2 W m(-2) was simulated, corresponding to a strong cooling effect. To optimize the cooling and minimize the amount of seeding material, globally nonuniform seeding strategies were tested, with minimal seeding in the summer hemisphere and in the tropics. With seeding applied to less than half the globe, an even stronger reduction in the NCF was achieved. This suggests that the CEM could work for an atmosphere even with considerable heterogeneous ice nucleation and that the desired cooling could be obtained without seeding the entire globe.",
"Key Points Cirrus cloud seeding in the upper troposphere was simulated in CAM5 Both cirrus cloud susceptibility and short-term climate response were analyzed Even globally non-uniform injection of IN leads to the desired cooling"
],
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES",
"affiliations": [
"Yale Univ, Dept Geol & Geophys, New Haven, CT 06520 USA",
"ETH, Inst Atmospher & Climate Sci, Zurich, Switzerland"
],
"countries": [
"USA",
"Switzerland"
],
"keywords": [
"COMMUNITY ATMOSPHERE MODEL",
"RELATIVE-HUMIDITY",
"INCA EXPERIMENT",
"CLIMATE",
"AEROSOLS",
"NUCLEATION",
"MECHANISMS",
"EMISSIONS",
"CAM5"
],
"subjects": [
"Meteorology & Atmospheric Sciences"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000333885700020",
"title": "What controls the interannual variation of the wet season onsets over the Amazon?",
"abstract": [
"Previous studies have established that sea surface temperature anomalies (SSTAs) in the tropical Pacific and Atlantic are the main forcing of the interannual variation of the wet season onsets in the Amazon. However, this variation appears to be complex and not uniquely determined by SSTAs. What causes such a complexity and to what extent the interannual variation of the wet season onsets is predictable remain unclear. This study suggests that such a complex relationship is the result of several competing processes, which are nonlinearly related to the SSTAs. In particular, three dry season conditions are crucial for determining interannual variation of the wet season onset. (i) A poleward shift of the Southern Hemisphere subtropical jet (SHSJ) over the South American sector, initiated from a wave train-like structure possibly forced by south central Pacific SST patterns, can prevent cold frontal systems from moving northward into the Amazon. This delays cold air incursion and results in late wet season onset over the southern Amazon. (ii) An anomalous anticyclonic center, which enhances westerly wind at 850hPa over the southern Amazon and also the South American low-level jets, leads to moisture export from the southern Amazon to La Plata basin and reduces convective systems that provide elevated diabatic heating. (iii) Smaller convective available potential energy (CAPE) limits local thermodynamically driven convection. Based on the stepwise and partial least squares regressions, these three selected preseasonal conditions (Nino 4, SHSJ, and CAPE) can explain 57% of the total variance of the wet season onset.",
"Key Points",
" The wet season onset over the Amazon is not uniquely deterimined by SSTAs A poleward SHSJ, enhanced U850, and lower CAPE are crucial for delayed onset Selected conditions can explain 57% of the total variance"
],
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES",
"affiliations": [
"Univ Texas Austin, Dept Geol Sci, Jackson Sch Geosci, Austin, TX 78712 USA",
"Univ Texas Austin, Coll Nat Sci, Dept Stat & Data Sci, Austin, TX 78712 USA",
"Univ Antioquia, Grp Ingn & Gest Ambiental, Medellin, Colombia",
"Univ Corp Atmospher Res, Visiting Scientist Programs, Boulder, CO USA",
"Texas Water Dev Board, Surface Water Resources Div, Austin, TX USA",
"Duke Univ, Nicholas Sch Environm, Div Earth & Ocean Sci, Durham, NC 27708 USA",
"Columbia Univ, Int Res Inst Climate & Soc, Palisades, NY USA"
],
"countries": [
"USA",
"Colombia"
],
"keywords": [
"CROSS-EQUATORIAL FLOW",
"COLD-AIR INCURSIONS",
"LOW-LEVEL JET",
"SOUTH-AMERICA",
"SURFACE-TEMPERATURE",
"LAND-SURFACE",
"ATMOSPHERE INTERACTION",
"TROPICAL ATLANTIC",
"NORTHEAST BRAZIL",
"RAINY-SEASON"
],
"subjects": [
"Meteorology & Atmospheric Sciences"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000332994600014",
"title": "Arctic cryosphere response in the Geoengineering Model Intercomparison Project G3 and G4 scenarios",
"abstract": "We analyzed output from the Geoengineering Model Intercomparison Project for the two most realistic scenarios, which use the representative concentration pathway of 4.5 Wm(-2) by 2100 (RCP4.5) as the control run and inject sulfate aerosol precursors into the stratosphere. The first experiment, G3, is specified to keep RCP4.5 top of atmosphere net radiation at 2020 values by injection of sulfate aerosols, and the second, G4, injects 5 Tg SO2 per year. We ask whether geoengineering by injection of sulfate aerosols into the lower stratosphere from the years 2020 to 2070 is able to prevent the demise of Northern Hemispere minimum annual sea ice extent or slow spring Northern Hemispere snow cover loss. We show that in all available models, despite geoengineering efforts, September sea ice extents still decrease from 2020 to 2070, although not as quickly as in RCP4.5. In two of five models, total September ice loss occurs before 2060. Spring snow extent is increased from 2020 to 2070 compared to RCP4.5 although there is still a negative trend in 3 of 4 models. Because of the climate system lag in responding to the existing radiative forcing, to stop Arctic sea ice and snow from continuing to melt, the imposed forcing would have to be large enough to also counteract the existing radiative imbalance. After the cessation of sulfate aerosol injection in 2070, the climate system rebounds to the warmer RCP4.5 state quickly, and thus, any sea ice or snow retention as a result of geoengineering is lost within a decade.",
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES",
"affiliations": [
"Rutgers State Univ, Dept Environm Sci, New Brunswick, NJ 08903 USA",
"Beijing Normal Univ, Coll Global Change & Earth Syst Sci, State Key Lab Earth Surface Proc & Resource, Beijing 100875, Peoples R China",
"Met Off Hadley Ctr, Exeter, Devon, England",
"Pacific NW Natl Lab, Atmospher Sci & Global Change Div, Richland, WA 99352 USA",
"Japan Agcy Marine Earth Sci & Technol, Yokohama, Kanagawa, Japan"
],
"countries": [
"USA",
"Peoples R China",
"England",
"Japan"
],
"keywords": [
"SEA-ICE",
"SNOW COVER",
"CLIMATE",
"TEMPERATURE",
"SIMULATIONS",
"VARIABILITY"
],
"subjects": [
"Meteorology & Atmospheric Sciences"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000332994600006",
"title": "A worldwide analysis of spatiotemporal changes in water balance-based evapotranspiration from 1982 to 2009",
"abstract": "A satellite-based water balance method is developed to model global evapotranspiration (ET) through coupling a water balance (WB) model with a machine-learning algorithm (the model tree ensemble, MTE) (hereafter WB-MTE). The WB-MTE algorithm was firstly trained by combining monthly WB-estimated basin ET with the potential drivers (e.g., radiation, temperature, precipitation, wind speed, and vegetation index) across 95 large river basins (5824 basin-months) and then applied to establish global monthly ET maps at a spatial resolution of 0.5 degrees from 1982 to 2009. The global land ET estimated from WB-MTE has an annual mean of 59317mm for 1982-2009, with a spatial distribution consistent with previous studies in all latitudes but the tropics. The ET estimated by WB-MTE also shows significant linear trends in both annual and seasonal global ET during 1982-2009, though the trends seem to have stalled after 1998. Moreover, our study presents a striking difference from the previous ones primarily in the magnitude of ET estimates during the wet season particularly in the tropics, where ET is highly uncertain due to lack of direct measurements. This may be tied to their lack of proper consideration to solar radiation and/or the rainfall interception process. By contrast, in the dry season, our estimate of ET compares well with the previous ones, both for the mean state and the variability. If we are to reduce the uncertainties in estimating ET, these results emphasize the necessity of deploying more observations during the wet season, particularly in the tropics.",
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES",
"affiliations": [
"Peking Univ, Coll Urban & Environm Sci, Beijing 100871, Peoples R China",
"CEA CNRS UVSQ, Lab Sci Climat & Environm, Paris, France",
"Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA",
"Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing, Peoples R China"
],
"countries": [
"Peoples R China",
"France",
"USA"
],
"keywords": [
"TROPICAL RAIN-FOREST",
"SOIL-MOISTURE",
"SURFACE-TEMPERATURE",
"GLOBAL ENERGY",
"EVAPORATION",
"PRECIPITATION",
"TRENDS",
"MODEL",
"VARIABILITY",
"FLUXNET"
],
"subjects": [
"Meteorology & Atmospheric Sciences"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000332991000061",
"title": "Simulating global and local surface temperature changes due to Holocene anthropogenic land cover change",
"abstract": "Surface albedo changes from anthropogenic land cover change (ALCC) represent the second largest negative radiative forcing behind aerosol during the industrial era. Using a new reconstruction of ALCC during the Holocene era by Kaplan et al. (2011), we quantify the local and global temperature response induced by Holocene ALCC in the Community Climate System Model, version 4. We find that Holocene ALCC causes a global cooling of 0.17 degrees C due to the biogeophysical effects of land-atmosphere exchange of momentum, moisture, and radiative and heat fluxes. On the global scale, the biogeochemical effects of Holocene ALCC from carbon emissions dominate the biogeophysical effects by causing 0.9 degrees C global warming. The net effects of Holocene ALCC amount to a global warming of 0.73 degrees C during the preindustrial era, which is comparable to the similar to 0.8 degrees C warming during industrial times. On local to regional scales, such as parts of Europe, North America, and Asia, the biogeophysical effects of Holocene ALCC are significant and comparable to the biogeochemical effect.",
"publication_year": 2014,
"source": "GEOPHYSICAL RESEARCH LETTERS",
"affiliations": [
"Univ Wisconsin, Ctr Climat Res, Madison, WI 53706 USA",
"Univ Virginia, Dept Environm Sci, Charlottesville, VA 22903 USA",
"Univ Geneva, Inst Environm Sci, Geneva, Switzerland"
],
"countries": [
"USA",
"Switzerland"
],
"keywords": [
"CLIMATE-CHANGE",
"SCALE DEFORESTATION",
"CARBON-CYCLE",
"MODEL",
"SENSITIVITY",
"DYNAMICS",
"DATABASE",
"IMPACT"
],
"subjects": [
"Geosciences, Multidisciplinary",
"Geology"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000332991000059",
"title": "Surface warming patterns drive tropical rainfall pattern responses to CO2 forcing on all timescales",
"abstract": [
"Mechanisms behind regional tropical rainfall responses to CO2 forcing are examined in idealized climate model experiments, traceable to transient forcing scenarios. As previously shown, the pattern of the first-year response of dynamical precipitation change to an abrupt CO2 increase is similar to the century-scale response. It is demonstrated here that this similarity is driven by surface temperature pattern change, not a direct atmospheric circulation response to CO2. This confirms the Warmer get Wetter hypothesis, which emphasizes the role of sea surface temperature pattern change in driving regional tropical precipitation change. Future regional rainfall changes should thus be studied primarily in coupled ocean-atmosphere models.",
"Key Points",
" Regional tropical rainfall change is driven by surface warming patterns Land-sea warming contrasts can drive tropics-wide circulation change The direct CO2 effect is important for mean rainfall change, but not patterns"
],
"publication_year": 2014,
"source": "GEOPHYSICAL RESEARCH LETTERS",
"affiliations": [
"Met Off Hadley Ctr, Exeter, Devon, England"
],
"countries": [
"England"
],
"keywords": [
"PRECIPITATION",
"CIRCULATION"
],
"subjects": [
"Geosciences, Multidisciplinary",
"Geology"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000332991000048",
"title": "Is climate sensitivity related to dynamical sensitivity? A Southern Hemisphere perspective",
"abstract": "This study examines whether the spread in the climate sensitivity of Coupled Model Intercomparison Project Phase 5 (CMIP5) models also captures the spread in the Southern Hemisphere dynamical response to greenhouse gas forcing. Three metrics are proposed to quantify the dynamical sensitivity of the Southern Hemisphere: the poleward expansion of the Hadley circulation, the poleward expansion of the subtropical dry zone, and the poleward shift of the midlatitude jet. In the CMIP5 abrupt 4xCO(2) integrations, the expansion of the Hadley circulation is well correlated with climate sensitivity in all seasons; in contrast, the shifts in the subtropical dry zone and midlatitude jet are significantly correlated with climate sensitivity only in summer and fall. In winter, those responses are more strongly linked to the control climatology in each model. Thus, a narrow focus on traditional climate sensitivity alone might miss out on important features of the atmospheric circulation's response to increasing greenhouse gases, particularly in the extratropics.",
"publication_year": 2014,
"source": "GEOPHYSICAL RESEARCH LETTERS",
"affiliations": [
"Columbia Univ, Lamont Doherty Earth Observ, Palisades, NY 10964 USA",
"Columbia Univ, Dept Appl Phys & Appl Math, New York, NY USA",
"Columbia Univ, Dept Earth & Environm Sci, New York, NY USA"
],
"countries": [
"USA"
],
"keywords": [
"ATMOSPHERIC CIRCULATION",
"CMIP5"
],
"subjects": [
"Geosciences, Multidisciplinary",
"Geology"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000332990500046",
"title": "The dependence of transient climate sensitivity and radiative feedbacks on the spatial pattern of ocean heat uptake",
"abstract": [
"The effect of ocean heat uptake (OHU) on transient global warming is studied in a multimodel framework. Simple heat sinks are prescribed in shallow aquaplanet ocean mixed layers underlying atmospheric general circulation models independently and combined with CO2 forcing. Sinks are localized to either tropical or high latitudes, representing distinct modes of OHU found in coupled simulations. Tropical OHU produces modest cooling at all latitudes, offsetting only a fraction of CO2 warming. High-latitude OHU produces three times more global mean cooling in a strongly polar-amplified pattern. Global sensitivities in each scenario are set primarily by large differences in local shortwave cloud feedbacks, robust across models. Differences in atmospheric energy transport set the pattern of temperature change. Results imply that global and regional warming rates depend sensitively on regional ocean processes setting the OHU pattern, and that equilibrium climate sensitivity cannot be reliably estimated from transient observations.",
"Key Points",
"Climate response depends strongly on spatial pattern of ocean heat uptake Different radiative feedbacks govern transient and equilibrium CO2 warming Results are robust across an ensemble of aquaplanet climate models"
],
"publication_year": 2014,
"source": "GEOPHYSICAL RESEARCH LETTERS",
"affiliations": [
"SUNY Albany, Dept Atmospher & Environm Sci, Albany, NY 12222 USA",
"MIT, Dept Earth Atmospher & Planetary Sci, Cambridge, MA USA",
"Univ Washington, Dept Atmospher Sci, Seattle, WA 98195 USA",
"CALTECH, Div Geol & Planetary Sci, Pasadena, CA 91125 USA",
"Univ Chicago, Dept Geophys Sci, Chicago, IL 60637 USA"
],
"countries": [
"USA"
],
"keywords": [
"PHYSICAL PARAMETRIZATIONS",
"POLAR AMPLIFICATION",
"MODEL",
"AQUAPLANET"
],
"subjects": [
"Geosciences, Multidisciplinary",
"Geology"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000333138300008",
"title": "Interactive ozone induces a negative feedback in CO2- driven climate change simulations",
"abstract": "Interactively coupled climate chemistry models (CCMs) extend the number of feedback mechanisms in climate change simulations by including chemical feedback. In this study the radiative feedback from ozone changes on climate response and climate sensitivity is quantified for a series of simulations driven by CO2 increases on top of a present-day reference concentration level. Other possibly relevant feedback via atmospheric chemistry, e.g., via CH4 and (NO)-O-2, is not fully quantified in the CCM setup as their concentrations are essentially fixed at the surface. In case of a CO2-doubling simulation, the ozone feedback reduces the climate sensitivity parameter by 3.4%, from 0.70 K/(W m(-2)) without interactive chemistry to 0.68 K/(W m(-2)). In case of a 4*CO2 simulation, the reduction of the climate sensitivity parameter increases to 8.4%. An analysis of feedback reveals that the negative feedback of stratospheric ozone and the associated negative feedback change in stratospheric water vapor are mainly responsible for this damping. The feedback from tropospheric ozone changes is positive but much smaller. The nonlinearity in the climate sensitivity damping with increased CO2 concentrations is shown to be due to nonlinear feedback of ozone and stratospheric water vapor.",
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES",
"affiliations": [
"Deutsch Zentrum Luft & Raumfahrt, Inst Phys Atmosphare, Oberpfaffenhofen, Germany"
],
"countries": [
"Germany"
],
"keywords": [
"TECHNICAL NOTE",
"CIRCULATION",
"IMPACT",
"SENSITIVITY"
],
"subjects": [
"Meteorology & Atmospheric Sciences"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000333022700026",
"title": "Optimal fingerprinting under multiple sources of uncertainty",
"abstract": "Detection and attribution studies routinely use linear regression methods referred to as optimal fingerprinting. Within the latter methodological paradigm, it is usually recognized that multiple sources of uncertainty affect both the observations and the simulated climate responses used as regressors. These include for instance internal variability, climate model error, or observational error. When all errors share the same covariance, the statistical inference is usually performed with the so-called total least squares procedure, but to date no inference procedure is readily available in the climate literature to treat the general case where this assumption does not hold. Here we address this deficiency. After a brief outlook on the error-in-variable models literature, we describe an inference procedure based on likelihood maximization, inspired by a recent article dealing with a similar situation in geodesy. We evaluate the performance of our approach via an idealized test bed. We find the procedure to outperform existing procedures when the latter wrongly neglect some sources of uncertainty.",
"publication_year": 2014,
"source": "GEOPHYSICAL RESEARCH LETTERS",
"affiliations": [
"CNRS CONICET UBA, IFAECI, Buenos Aires, DF, Argentina",
"Meteo France CNRS, CNRM GAME, Toulouse, France",
"CNRS CEA, IPSL, LSCE, Saclay, France"
],
"countries": [
"Argentina",
"France"
],
"keywords": "MODELS",
"subjects": [
"Geosciences, Multidisciplinary",
"Geology"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000332990200025",
"title": "Influence of the Atlantic Meridional Overturning Circulation on the monsoon rainfall and carbon balance of the American tropics",
"abstract": "We examine the response of the American Tropics to changes in Atlantic Meridional Overturning Circulation (AMOC) strength using a set of water-hosing experiments with an Earth system model that explicitly simulates the global and regional carbon cycle. We find that a moderate weakening (27%) of the AMOC, induced by a 0.1Sv (1Sv10(6)m(3)s(-1)) freshwater addition in the northern North Atlantic, drives small but statistically significant drying in the South American monsoon region. By contrast, a complete shutdown of the AMOC, induced by a 1.0Sv freshwater addition, acts to considerably shift the ITCZ southward, which changes the seasonal cycle of precipitation over Amazonia. Our results indicate that AMOC weakening can have a significant impact on the terrestrial primary productivity and carbon storage of the American Tropics.",
"publication_year": 2014,
"source": "GEOPHYSICAL RESEARCH LETTERS",
"affiliations": [
"Univ Arizona, Dept Geosci, Tucson, AZ 85721 USA",
"NOAA, Geophys Fluid Dynam Lab, Princeton, NJ USA",
"Princeton Univ, Dept Ecol & Evolutionary Biol, Princeton, NJ 08544 USA"
],
"countries": [
"USA"
],
"keywords": [
"THERMOHALINE CIRCULATION",
"AMAZON BASIN",
"CLIMATE VARIABILITY",
"SIMULATION",
"FORMULATION",
"STORAGE",
"MODELS"
],
"subjects": [
"Geosciences, Multidisciplinary",
"Geology"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000337607900006",
"title": "Emergent constraints on climate-carbon cycle feedbacks in the CMIP5 Earth system models",
"abstract": "An emergent linear relationship between the long-term sensitivity of tropical land carbon storage to climate warming (LT) and the short-term sensitivity of atmospheric carbon dioxide (CO2) to interannual temperature variability (IAV) has previously been identified by Cox et al. (2013) across an ensemble of Earth system models (ESMs) participating in the Coupled Climate-Carbon Cycle Model Intercomparison Project (C4MIP). Here we examine whether such a constraint also holds for a new set of eight ESMs participating in Phase 5 of the Coupled Model Intercomparison Project. A wide spread in tropical land carbon storage is found for the quadrupling of atmospheric CO2, which is of the order of 252 +/- 112 GtC when carbon-climate feedbacks are enabled. Correspondingly, the spread in LT is wide (-49 +/- 40 GtC/K) and thus remains one of the key uncertainties in climate projections. A tight correlation is found between the long-term sensitivity of tropical land carbon and the short-term sensitivity of atmospheric CO2 (LT versus IAV), which enables the projections to be constrained with observations. The observed short-term sensitivity of CO2 (-4.4 +/- 0.9 GtC/yr/K) sharpens the range of LT to -44 +/- 14 GtC/K, which overlaps with the probability density function derived from the C4MIP models (-53 +/- 17 GtC/K) by Cox et al. (2013), even though the lines relating LT and IAV differ in the two cases. Emergent constraints of this type provide a means to focus ESM evaluation against observations on the metrics most relevant to projections of future climate change.",
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES",
"affiliations": [
"Deutsch Zentrum Luft & Raumfahrt, Inst Phys Atmosphare, Oberpfaffenhofen, Germany",
"Univ Exeter, Coll Engn Math & Phys Sci, Exeter EX4 4QJ, Devon, England"
],
"countries": [
"Germany",
"England"
],
"keywords": [
"GLOBAL VEGETATION MODEL",
"LAND",
"SENSITIVITY",
"BIOSPHERE",
"DIOXIDE",
"FUTURE",
"PRODUCTIVITY",
"SIMULATIONS",
"REDUCTION",
"EXTREMES"
],
"subjects": [
"Environmental Sciences",
"Geosciences, Multidisciplinary",
"Environmental Sciences & Ecology",
"Geology"
],
"subheadings": [
"Life Sciences & Biomedicine",
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000334908300017",
"title": "A multimodel examination of climate extremes in an idealized geoengineering experiment",
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES",
"affiliations": [
"Univ Victoria, Sch Earth & Ocean Sci, Victoria, BC, Canada",
"Univ Oslo, Dept Geosci, Oslo, Norway",
"Pacific Climate Impacts Consortium, Victoria, BC, Canada",
"Environm Canada, Canadian Ctr Climate Modelling & Anal, Toronto, ON, Canada",
"Beijing Normal Univ, State Key Lab Earth Surface Proc & Resource Ecol, Coll Global Change & Earth Syst Sci, Beijing 100875, Peoples R China",
"Pacific NW Natl Lab, Richland, WA 99352 USA",
"Max Planck Inst Meteorol, D-20146 Hamburg, Germany",
"Rutgers State Univ, Dept Environm Sci, New Brunswick, NJ 08903 USA",
"Natl Ctr Atmospher Res, Boulder, CO 80307 USA",
"Danish Meteorol Inst, Copenhagen, Denmark"
],
"countries": [
"Canada",
"Norway",
"Peoples R China",
"USA",
"Germany",
"Denmark"
],
"keywords": [
"MONITORING CHANGES",
"SEASONAL CYCLE",
"PRECIPITATION",
"TEMPERATURE",
"MODEL",
"ENSEMBLE",
"INDEXES",
"RESPONSES",
"SCHEMES",
"IMPACT"
],
"subjects": [
"Meteorology & Atmospheric Sciences"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000334908300040",
"title": "Ammonia emissions in the United States, European Union, and China derived by high-resolution inversion of ammonium wet deposition data: Interpretation with a new agricultural emissions inventory (MASAGE_NH3)",
"publication_year": 2014,
"source": "JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES",
"affiliations": [
"Harvard Univ, Sch Engn & Appl Sci, Cambridge, MA 02138 USA",
"US EPA, Off Res & Dev, Res Triangle Pk, NC 27711 USA",
"Univ Colorado, Dept Mech Engn, Boulder, CO 80309 USA"
],
"countries": [
"USA"
],
"keywords": [
"NITROGEN DEPOSITION",
"AIR-QUALITY",
"ATMOSPHERIC AMMONIA",
"DAIRY-COWS",
"MODEL",
"PARAMETERIZATION",
"ADJOINT",
"SULFATE",
"AEROSOL",
"POLLUTION"
],
"subjects": [
"Meteorology & Atmospheric Sciences"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000334983000034",
"title": "How deep is deep enough? Ocean iron fertilization and carbon sequestration in the Southern Ocean",
"abstract": "Artificial ocean iron fertilization (OIF) enhances phytoplankton productivity and is being explored as a means of sequestering anthropogenic carbon within the deep ocean. To be considered successful, carbon should be exported from the surface ocean and isolated from the atmosphere for an extended period (e.g., the Intergovernmental Panel on Climate Change's standard 100 year time horizon). This study assesses the impact of deep circulation on carbon sequestered by OIF in the Southern Ocean, a high-nutrient low-chlorophyll region known to be iron stressed. A Lagrangian particle-tracking approach is employed to analyze water mass trajectories over a 100 year simulation. By the end of the experiment, for a sequestration depth of 1000 m, 66% of the carbon had been reexposed to the atmosphere, taking an average of 37.8 years. Upwelling occurs predominately within the Antarctic Circumpolar Current due to Ekman suction and topography. These results emphasize that successful OIF is dependent on the physical circulation, as well as the biogeochemistry.",
"publication_year": 2014,
"source": "GEOPHYSICAL RESEARCH LETTERS",
"affiliations": [
"Univ Southampton, Southampton, Hants, England",
"Natl Oceanog Ctr, Southampton, Hants, England"
],
"countries": [
"England"
],
"keywords": "EFFICIENCY",
"subjects": [
"Geosciences, Multidisciplinary",
"Geology"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000334983000052",
"title": "Recent and future trends in synthetic greenhouse gas radiative forcing",
"abstract": "Atmospheric measurements show that emissions of hydrofluorocarbons (HFCs) and hydrochlorofluorocarbons are now the primary drivers of the positive growth in synthetic greenhouse gas (SGHG) radiative forcing. We infer recent SGHG emissions and examine the impact of future emissions scenarios, with a particular focus on proposals to reduce HFC use under the Montreal Protocol. If these proposals are implemented, overall SGHG radiative forcing could peak at around 355mWm(-2) in 2020, before declining by approximately 26% by 2050, despite continued growth of fully fluorinated greenhouse gas emissions. Compared to no HFC policy projections, this amounts to a reduction in radiative forcing of between 50 and 240mWm(-2) by 2050 or a cumulative emissions saving equivalent to 0.5 to 2.8years of CO2 emissions at current levels. However, more complete reporting of global HFC emissions is required, as less than half of global emissions are currently accounted for.",
"publication_year": 2014,
"source": "GEOPHYSICAL RESEARCH LETTERS",
"affiliations": [
"Univ Bristol, Sch Chem, Bristol, Avon, England",
"MIT, Ctr Global Change Sci, Cambridge, MA 02139 USA",
"NOAA, Earth Syst Res Lab, Boulder, CO USA",
"MIT, Dept Earth Atmospher & Planetary Sci, Cambridge, MA USA",
"Univ Calif San Diego, Scripps Inst Oceanog, La Jolla, CA 92093 USA",
"CSIRO Marine & Atmospher Res, Ctr Australian Weather & Climate Res, Aspendale, Vic, Australia"
],
"countries": [
"England",
"USA",
"Australia"
],
"keywords": [
"IN-SITU MEASUREMENTS",
"MONTREAL PROTOCOL",
"HYDROFLUOROCARBONS",
"PERFLUOROCARBONS",
"ATMOSPHERE",
"LIFETIMES",
"EMISSIONS",
"HISTORY",
"STATION",
"GROWTH"
],
"subjects": [
"Geosciences, Multidisciplinary",
"Geology"
],
"subheadings": [
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
},
{
"uri": "WOS:000358132500001",
"title": "Multidecadal global cooling and unprecedented ozone loss following a regional nuclear conflict",
"abstract": "We present the first study of the global impacts of a regional nuclear war with an Earth system model including atmospheric chemistry, ocean dynamics, and interactive sea ice and land components. A limited, regional nuclear war between India and Pakistan in which each side detonates 50 15 kt weapons could produce about 5 Tg of black carbon (BC). This would self-loft to the stratosphere, where it would spread globally, producing a sudden drop in surface temperatures and intense heating of the stratosphere. Using the Community Earth System Model with the Whole Atmosphere Community Climate Model, we calculate an e-folding time of 8.7 years for stratospheric BC compared to 4-6.5 years for previous studies. Our calculations show that global ozone losses of 20%-50% over populated areas, levels unprecedented in human history, would accompany the coldest average surface temperatures in the last 1000 years. We calculate summer enhancements in UV indices of 30%-80% over midlatitudes, suggesting widespread damage to human health, agriculture, and terrestrial and aquatic ecosystems. Killing frosts would reduce growing seasons by 10-40 days per year for 5 years. Surface temperatures would be reduced for more than 25 years due to thermal inertia and albedo effects in the ocean and expanded sea ice. The combined cooling and enhanced UV would put significant pressures on global food supplies and could trigger a global nuclear famine. Knowledge of the impacts of 100 small nuclear weapons should motivate the elimination of more than 17,000 nuclear weapons that exist today.",
"publication_year": 2014,
"source": "EARTHS FUTURE",
"affiliations": [
"NCAR Earth Syst Lab, Boulder, CO 80307 USA",
"Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80309 USA",
"Univ Colorado, Dept Atmospher & Ocean Sci, Boulder, CO 80309 USA",
"Rutgers State Univ, Dept Environm Sci, New Brunswick, NJ 08903 USA"
],
"countries": [
"USA"
],
"keywords": [
"SOLAR ULTRAVIOLET-RADIATION",
"DESCRIBING AEROSOL FORMATION",
"CLIMATE-CHANGE",
"MODEL",
"CONSEQUENCES",
"STRATOSPHERE",
"EVOLUTION",
"EXPOSURE",
"IMPACTS",
"WINTER"
],
"subjects": [
"Environmental Sciences",
"Geosciences, Multidisciplinary",
"Meteorology & Atmospheric Sciences",
"Environmental Sciences & Ecology",
"Geology"
],
"subheadings": [
"Life Sciences & Biomedicine",
"Physical Sciences"
],
"headings": [
"Science & Technology"
]
}]
