A5041365196- Atmospheric Ozone and Climate
- Atmospheric and Environmental Gas Dynamics
- Atmospheric chemistry and aerosols
- Climate variability and models
- Meteorological Phenomena and Simulations
- Ionosphere and magnetosphere dynamics
- Geophysics and Gravity Measurements
- Air Quality Monitoring and Forecasting
- Solar and Space Plasma Dynamics
- Hydrocarbon exploration and reservoir analysis
- Atmospheric aerosols and clouds
- Air Quality and Health Impacts
- Tropical and Extratropical Cyclones Research
- Vehicle emissions and performance
- Climate Change and Health Impacts
- Oceanographic and Atmospheric Processes
- Methane Hydrates and Related Phenomena
- Calibration and Measurement Techniques
- CO2 Sequestration and Geologic Interactions
- Ocean Acidification Effects and Responses
- Geochemistry and Geologic Mapping
- COVID-19 impact on air quality
- Arctic and Antarctic ice dynamics
- Radioactive contamination and transfer
- Astro and Planetary Science
Goddard Space Flight Center
2016-2025
Science Systems and Applications (United States)
2018-2024
Langley Research Center
2024
National Aeronautics and Space Administration
2024
Universities Space Research Association
1998-2022
Morgan State University
2018-2022
Johns Hopkins University
2008-2016
Cooperative Institute for Research in Environmental Sciences
2016
NOAA Earth System Research Laboratory
2016
Physical Sciences (United States)
2016
The Modern-Era Retrospective Analysis for Research and Applications, version 2 (MERRA-2), is the latest atmospheric reanalysis of modern satellite era produced by NASA’s Global Modeling Assimilation Office (GMAO). MERRA-2 assimilates observation types not available to its predecessor, MERRA, includes updates Goddard Earth Observing System (GEOS) model analysis scheme so as provide a viable ongoing climate beyond MERRA’s terminus. While addressing known limitations also intended be...
Abstract The Modern-Era Retrospective Analysis for Research and Applications (MERRA) was undertaken by NASA’s Global Modeling Assimilation Office with two primary objectives: to place observations from Earth Observing System satellites into a climate context improve upon the hydrologic cycle represented in earlier generations of reanalyses. Focusing on satellite era, 1979 present, MERRA has achieved its goals significant improvements precipitation water vapor climatology. Here, brief...
Global satellite observations of temperature and geopotential height (GPH) from the Microwave Limb Sounder (MLS) on EOS Aura spacecraft are discussed. The precision, resolution, accuracy data produced by MLS version 2.2 processing algorithms quantified, recommendations for screening made. Temperature precision is 1 K or better 316 hPa to 3.16 hPa, degrading ∼3 at 0.001 hPa. vertical resolution 3 km 31.6 6 ∼13 Comparisons with analyses (Goddard Earth Observing System 5.0.1 (GEOS‐5), European...
A major stratospheric sudden warming (SSW) in January 2009 was the strongest and most prolonged on record. Aura Microwave Limb Sounder (MLS) observations are used to provide an overview of dynamics transport during SSW, compare with intense, long‐lasting SSW 2006. The Arctic polar vortex split whereas 2006 a displacement event. Winds reversed easterly more rapidly reverted westerly slowly than More mixing trace gases out decay fragments, less before fulfillment criteria, seen 2006;...
Precision requirements are determined for space‐based column‐averaged CO 2 dry air mole fraction data. These result from an assessment of spatial and temporal gradients in the relationship between precision surface flux uncertainties inferred inversions data, effects biases on fidelity inversions. Observational system simulation experiments synthesis inversion modeling demonstrate that Orbiting Carbon Observatory mission design sampling strategy provide means to achieve these data requirements.
Simulations from eleven coupled chemistry‐climate models (CCMs) employing nearly identical forcings have been used to project the evolution of stratospheric ozone throughout 21st century. The model‐to‐model agreement in projected temperature trends is good, and all CCMs predict continued, global mean cooling stratosphere over next 5 decades, increasing around 0.25 K/decade at 50 hPa 1 under Intergovernmental Panel on Climate Change (IPCC) Special Report Emissions Scenarios (SRES) A1B...
In the past several decades, tropospheric westerly winds in Southern Hemisphere have been observed to accelerate on poleward side of surface wind maximum. This has attributed combined anthropogenic effects increasing greenhouse gases and decreasing stratospheric ozone is predicted continue by Intergovernmental Panel Climate Change/Fourth Assessment Report (IPCC/AR4) models. this paper, predictions Chemistry-Climate Model Validation (CCMVal) models are examined: Unlike AR4 models, CCMVal a...
Abstract. The climate research community uses atmospheric reanalysis data sets to understand a wide range of processes and variability in the atmosphere, yet different reanalyses may give very results for same diagnostics. Stratosphere–troposphere Processes And their Role Climate (SPARC) Reanalysis Intercomparison Project (S-RIP) is coordinated activity compare using variety key objectives this project are identify differences among underlying causes, provide guidance on appropriate usage...
Abstract The response of stratospheric climate and circulation to increasing amounts greenhouse gases (GHGs) ozone recovery in the twenty-first century is analyzed simulations 11 chemistry–climate models using near-identical forcings experimental setup. In addition an overall global cooling stratosphere (0.59 ± 0.07 K decade−1 at 10 hPa), causes a warming Southern Hemisphere polar lower summer with enhanced above. rate correlates projected by and, on average, changes from 0.8 0.48 100 hPa as...
Abstract. We describe the Harvard–NASA Emission Component version 1.0 (HEMCO), a stand-alone software component for computing emissions in global atmospheric models. HEMCO determines from different sources, regions, and species on user-defined grid can combine, overlay, update set of data inventories scale factors, as specified by user through configuration file. New emission at any spatial temporal resolution are readily added to be accessed without preprocessing files or modification...
Satellite data of atmospheric pollutants are becoming more widely used in the decision-making and environmental management activities public, private sector non-profit organizations. They employed for estimating emissions, tracking pollutant plumes, supporting air quality forecasting activities, providing evidence "exceptional event" declarations, monitoring regional long-term trends, evaluating model output. However, many managers not taking full advantage these applications nor has...
The assimilated ozone product from the Modern-Era Retrospective Analysis for Research and Applications, version 2 (MERRA-2), produced at NASA’s Global Modeling Assimilation Office (GMAO) spanning time period 1980 to present is described herein, its quality assessed. MERRA-2 assimilates partial column retrievals a series of Solar Backscatter Ultraviolet Radiometer (SBUV) instruments on NASA NOAA spacecraft between January September 2004: starting in October 2004, retrieved profiles Microwave...
Abstract The quasi‐biennial oscillation (QBO) is a tropical lower stratospheric, downward propagating zonal wind variation, with an average period of ~28 months. QBO has been constantly documented since 1953. Here we describe the evolution during Northern Hemisphere winter 2015–2016 using radiosonde observations and meteorological reanalyses. Normally, would show steady propagation westerly phase. In 2015–2016, there was anomalous upward displacement this phase from ~30 hPa to 15 hPa. These...
The Goddard Earth Observing System composition forecast (GEOS-CF) system is a high-resolution (0.25°) global constituent prediction from NASA's Global Modeling and Assimilation Office (GMAO). GEOS-CF offers new tool for atmospheric chemistry research, with the goal to supplement broad range of space-based in-situ observations. expands on GEOS weather aerosol modeling by introducing GEOS-Chem module provide hindcasts 5-days forecasts constituents including ozone (O
Abstract. Social distancing to combat the COVID-19 pandemic has led widespread reductions in air pollutant emissions. Quantifying these changes requires a business-as-usual counterfactual that accounts for synoptic and seasonal variability of pollutants. We use machine learning algorithm driven by information from NASA GEOS-CF model assess nitrogen dioxide (NO2) ozone (O3) at 5756 observation sites 46 countries January through June 2020. Reductions NO2 coincide with timing intensity...
Abstract. In recent years a number of chemistry-climate models have been developed with an emphasis on the stratosphere. Such cover wide range time scales integration and vary considerably in complexity. The results specific diagnostics are here analysed to examine differences amongst individual observations, assess consistency model predictions, particular focus polar ozone. For example, many indicate significant cold bias high latitudes, "cold pole problem", particularly southern...
The 2003–2004 Arctic winter was remarkable in the ∼50‐year record of meteorological analyses. A major warming beginning early January 2004 led to nearly 2 months vortex disruption with high‐latitude easterlies middle lower stratosphere. upper stratospheric broke up late December, but began recover by January, and February March strongest since regular observations 1979. January. Comparison previous years, 1984–1985 1986–1987, prolonged midwinter periods shows unique characteristics period:...
Microwave Limb Sounder and Sounding of the Atmosphere with Broadband Emission Radiometry data provide first opportunity to characterize four‐dimensional stratopause evolution throughout life‐cycle a major stratospheric sudden warming (SSW). The polar stratopause, usually higher than that at midlatitudes, dropped by ∼30 km warmed during development “wave 1” SSW in January 2006, accompanying mesospheric cooling. When vortex broke down, cooled became ill‐defined, nearly isothermal stratosphere....
The persistence of the Arctic and Antarctic lower stratospheric vortices is examined over period from 1958 to 1999. Three different vortex‐following diagnostics (two using potential vorticity one based solely on zonal winds) are compared shown give very similar results for breakup date. variability in timing both qualitatively same: There large interannual variations together with smaller decadal‐scale there a significant increase since mid‐1980s (all larger vortex). Also, hemispheres, high...
Abstract. Projections of stratospheric ozone from a suite chemistry-climate models (CCMs) have been analyzed. In addition to reference simulation where anthropogenic halogenated depleting substances (ODSs) and greenhouse gases (GHGs) vary with time, sensitivity simulations either ODS or GHG concentrations fixed at 1960 levels were performed disaggregate the drivers projected changes. These also used assess two distinct milestones returning historical values (ozone return dates) no longer...
Model experiments have revealed that stratospheric polar ozone depletion and anthropogenic increase of greenhouse gases (GHG) both contributed to the observed summertime tropospheric westerlies in Southern Hemisphere (SH) with influence dominating. As halogen loading decreases future, is expected return higher values, disappearance Antarctic hole. The impact this recovery on SH climate investigated using 21st century simulations a chemistry model (CCM). response by 2100 shows circulation...
Abstract. Ozone depletion by chlorofluorocarbons (CFCs) was first proposed Molina and Rowland in their 1974 Nature paper. Since that time, the scientific connection between ozone losses CFCs other depleting substances (ODSs) has been firmly established with laboratory measurements, atmospheric observations, modeling studies. This science research led to implementation of international agreements largely stopped production ODSs. In this study we use a fully-coupled...
[1] The stratospheric climate and variability from simulations of sixteen chemistry-climate models is evaluated. On average the polar night jet well reproduced though its less with a large spread between models. Polar temperature biases are than 5 K except in Southern Hemisphere (SH) lower stratosphere spring. accumulated area low temperatures responsible for cloud formation accurately Antarctic but underestimated Arctic. shape position vortex simulated, as tropical upwelling stratosphere....