A5110702241- Atmospheric chemistry and aerosols
- Atmospheric Ozone and Climate
- Atmospheric aerosols and clouds
- Atmospheric and Environmental Gas Dynamics
- Air Quality and Health Impacts
- Climate variability and models
- Meteorological Phenomena and Simulations
- Air Quality Monitoring and Forecasting
- Cryospheric studies and observations
- Geology and Paleoclimatology Research
- Planetary Science and Exploration
- Methane Hydrates and Related Phenomena
- Radioactivity and Radon Measurements
- Arctic and Antarctic ice dynamics
- Tropical and Extratropical Cyclones Research
- Astro and Planetary Science
- Climate change and permafrost
- Geomagnetism and Paleomagnetism Studies
- Peatlands and Wetlands Ecology
- Geophysics and Gravity Measurements
- Vehicle emissions and performance
- Aeolian processes and effects
- Climate Change Policy and Economics
- Geological Modeling and Analysis
- Electrohydrodynamics and Fluid Dynamics
NOAA Weather Program Office
2022
NOAA Oceanic and Atmospheric Research
2022
National Oceanic and Atmospheric Administration
2022
Office of Science
2013-2018
NOAA National Weather Service Office of Science and Technology Integration
2018
United States Department of Energy
2011-2017
Columbia University
2005-2015
Goddard Institute for Space Studies
2004-2014
Earth Island Institute
2005-2011
National Aeronautics and Space Administration
2003-2010
Abstract Black carbon aerosol plays a unique and important role in Earth's climate system. is type of carbonaceous material with combination physical properties. This assessment provides an evaluation black‐carbon forcing that comprehensive its inclusion all known relevant processes quantitative providing best estimates uncertainties the main terms: direct solar absorption; influence on liquid, mixed phase, ice clouds; deposition snow ice. These effects are calculated models, but when...
We use a global climate model to compare the effectiveness of many forcing agents for producing change. find substantial range in “efficacy” different forcings, where efficacy is temperature response per unit relative CO 2 forcing. Anthropogenic CH 4 has ∼110%, which increases ∼145% when its indirect effects on stratospheric H O and tropospheric 3 are included, yielding an effective ∼0.8 W/m period 1750–2000 making largest anthropogenic other than . Black carbon (BC) aerosols from biomass...
Abstract. Simulation results of global aerosol models have been assembled in the framework AeroCom intercomparison exercise. In this paper, we analyze life cycles dust, sea salt, sulfate, black carbon and particulate organic matter as simulated by sixteen models. The differences among (model diversities) for sources sinks, burdens, particle sizes, water uptakes, spatial dispersals established. These diversities large consequences calculated radiative forcing concentrations at surface....
Abstract. This study presents the results of a broad intercomparison total 15 global aerosol models within AeroCom project. Each model is compared to observations related desert dust aerosols, their direct radiative effect, and impact on biogeochemical cycle, i.e., optical depth (AOD) deposition. Additional comparisons Angström exponent (AE), coarse mode AOD surface concentrations are included extend assessment performance identify common biases present in models. These data comprise...
Abstract A full description of the ModelE version Goddard Institute for Space Studies (GISS) atmospheric general circulation model (GCM) and results are presented present-day climate simulations (ca. 1979). This is a complete rewrite previous models incorporating numerous improvements in basic physics, stratospheric circulation, forcing fields. Notable changes include following: top now above stratopause, number vertical layers has increased, new cloud microphysical scheme used, vegetation...
Evaluating multicomponent climate change mitigation strategies requires knowledge of the diverse direct and indirect effects emissions. Methane, ozone, aerosols are linked through atmospheric chemistry so that emissions a single pollutant can affect several species. We calculated composition changes, historical radiative forcing, forcing per unit emission due to aerosol tropospheric ozone precursor in coupled composition-climate model. found gas-aerosol interactions substantially alter...
Our climate model, driven mainly by increasing human-made greenhouse gases and aerosols, among other forcings, calculates that Earth is now absorbing 0.85 +/- 0.15 watts per square meter more energy from the Sun than it emitting to space. This imbalance confirmed precise measurements of ocean heat content over past 10 years. Implications include (i) expectation additional global warming about 0.6 degrees C without further change atmospheric composition; (ii) confirmation system's lag in...
Abstract. The AeroCom exercise diagnoses multi-component aerosol modules in global modeling. In an initial assessment simulated distributions for mass and mid-visible optical thickness (aot) were compared among 20 different modules. Model diversity was also explored the context of previous comparisons. For component combined aot general agreement has improved annual mean. At 0.11 to 0.14, values are at lower end averages suggested by remote sensing from ground (AERONET ca. 0.135) space...
Abstract We present a description of the ModelE2 version Goddard Institute for Space Studies (GISS) General Circulation Model (GCM) and configurations used in simulations performed Coupled Intercomparison Project Phase 5 (CMIP5). use six variations related to treatment atmospheric composition, calculation aerosol indirect effects, ocean model component. Specifically, we test difference between models that have noninteractive where radiatively important aerosols ozone are prescribed from...
Abstract. Nine different global models with detailed aerosol modules have independently produced instantaneous direct radiative forcing due to anthropogenic aerosols. The impact is derived from the difference of two model simulations prescribed emissions, one for present-day and pre-industrial conditions. in solar energy budget at top atmosphere (ToA) yields a new harmonized estimate (RF) under all-sky On annual basis RF −0.22 Wm−2, ranging +0.04 −0.41 standard deviation ±0.16 Wm−2....
Abstract. Absorbing aerosols (AAs) such as black carbon (BC) or dust absorb incoming solar radiation, perturb the temperature structure of atmosphere, and influence cloud cover. Previous studies have described conditions under which AAs either increase decrease The effect depends on several factors, including altitude AA relative to type. We attempt categorize effects into likely regimes. Cloud cover is decreased if are embedded in layer. below may enhance convection above top stabilize...
Abstract. We evaluate black carbon (BC) model predictions from the AeroCom intercomparison project by considering diversity among year 2000 simulations and comparing with available measurements. These model-measurement intercomparisons include BC surface aircraft concentrations, aerosol absorption optical depth (AAOD) retrievals AERONET Ozone Monitoring Instrument (OMI) column estimations based on AERONET. In regions other than Asia, most models are biased high compared to concentration...
Abstract. We examine the response of Arctic gas and aerosol concentrations to perturbations in pollutant emissions from Europe, East South Asia, North America using results a coordinated model intercomparison. These sensitivities regional (mixing ratio change per unit emission) vary widely across models species. Intermodel differences are systematic, however, so that relative importance different regions is robust. contributes most ozone pollution. For aerosols CO, European dominate at...
<strong class="journal-contentHeaderColor">Abstract.</strong> This paper evaluates the current status of global modeling organic aerosol (OA) in troposphere and analyzes differences between models as well observations. Thirty-one chemistry transport (CTMs) general circulation (GCMs) have participated this intercomparison, framework AeroCom phase II. The simulation OA varies greatly terms magnitude primary emissions, secondary (SOA) formation, number species used (2 to 62), complexity...
Abstract. Aerosol indirect effects continue to constitute one of the most important uncertainties for anthropogenic climate perturbations. Within international AEROCOM initiative, representation aerosol-cloud-radiation interactions in ten different general circulation models (GCMs) is evaluated using three satellite datasets. The focus on stratiform liquid water clouds since GCMs do not include ice nucleation effects, and none model explicitly parameterises aerosol convective clouds. We...
Abstract. Several short-lived pollutants known to impact Arctic climate may be contributing the accelerated rates of warming observed in this region relative global annually averaged temperature increase. Here, we present a summary that including methane, tropospheric ozone, and aerosols. For each pollutant, provide description major sources mechanism forcing. We also first seasonally forcing corresponding response estimates focused specifically on Arctic. The calculations indicate forcings...
Black carbon (BC) particles, derived from incomplete combustion of fossil fuels and biomass, may have a severe impact on the sensitive Arctic climate, possibly altering temperature profile, cloud amount, seasonal cycle, tropopause level accelerating polar ice melting. We use Goddard Institute for Space Studies general circulation model to investigate origins BC by isolating various source regions types. The suggests that predominant sources soot today are south Asia (industrial biofuel...
Abstract. Nitrate aerosols are expected to become more important in the future atmosphere due increase nitrate precursor emissions and decline of ammonium-sulphate wide regions this planet. The GISS climate model is used study, including atmospheric gas- aerosol phase chemistry investigate current (2030, following SRES A1B emission scenario) compositions. A set sensitivity experiments was carried out quantify individual impact emission- physical change on formation. We found that loads...
Abstract. We investigate the issue of "dangerous human-made interference with climate" using simulations GISS modelE driven by measured or estimated forcings for 1880–2003 and extended to 2100 IPCC greenhouse gas scenarios as well "alternative" scenario Hansen Sato (2004). Identification "dangerous" effects is partly subjective, but we find evidence that added global warming more than 1°C above level in 2000 has may be highly disruptive. The alternative scenario, peak forcing ~1.5 W/m2 2100,...
A much-cited bar chart provided by the Intergovernmental Panel on Climate Change displays climate impact, as expressed radiative forcing in watts per meter squared, of individual chemical species. The organization reflects history atmospheric chemistry, which investigators typically focused a single species interest. However, changes pollutant emissions and concentrations are symptom, not cause , primary driver anthropogenic change: human activity. In this paper, we suggest organizing...
The CALIOP (Cloud‐Aerosol Lidar with Orthogonal Polarization) layer product is used for a multimodel evaluation of the vertical distribution aerosols. Annual and seasonal aerosol extinction profiles are analyzed over 13 sub‐continental regions representative industrial, dust, biomass burning pollution, from 2007–2009 observations AeroCom (Aerosol Comparisons between Observations Models) 2000 simulations. An mean height diagnostic (Z α ) defined to quantitatively assess models' performance....
We define the radiative forcings used in climate simulations with SI2000 version of Goddard Institute for Space Studies (GISS) global model. These include temporal variations well‐mixed greenhouse gases, stratospheric aerosols, solar irradiance, ozone, water vapor, and tropospheric aerosols. Our illustrations focus on period 1951–2050, but we make full data sets available those which have earlier data. illustrate response to these model specified sea surface temperature a simple Q ‐flux...
Global sulfate aerosol composition is simulated online in the Goddard Institute for Space Studies general circulation model II′ (GISS GCM II‐prime). Four sulfur species, hydrogen peroxide, gas phase ammonia, and particulate ammonium are prognostic tracer emissions, transport, deposition of which explicitly simulated. Nitric acid fields prescribed based on a global chemical transport model. An thermodynamic equilibrium calculation determines partitioning ammonia nitrate between phases,...
An on‐line simulation of aerosol sulfate, nitrate, ammonium, and water in the Goddard Institute for Space Studies general circulation model (GCM II‐prime) has been used to estimate direct radiative forcing years 1800, 2000, 2100. This is first based on equilibrium content a changing SO 4 2− ‐NO 3 − ‐NH + mixture nitrate global aerosol. Present‐day annual average anthropogenic estimated be −0.95 −0.19 W/m 2 sulfate respectively. Simulations with future emissions scenario indicate that could...