A5052513699- Atmospheric chemistry and aerosols
- Atmospheric Ozone and Climate
- Atmospheric and Environmental Gas Dynamics
- Air Quality and Health Impacts
- Air Quality Monitoring and Forecasting
- Atmospheric aerosols and clouds
- Vehicle emissions and performance
- Climate Change and Health Impacts
- COVID-19 impact on air quality
- Ionosphere and magnetosphere dynamics
- Space Exploration and Technology
- Space exploration and regulation
- Climate variability and models
- Water Quality Monitoring and Analysis
- Meteorological Phenomena and Simulations
- Fire effects on ecosystems
- Technology Assessment and Management
- Earthquake Detection and Analysis
- Geophysics and Gravity Measurements
- Spectroscopy and Laser Applications
- Methane Hydrates and Related Phenomena
- Advanced Aircraft Design and Technologies
- Advanced Chemical Sensor Technologies
- Plant responses to elevated CO2
- Lightning and Electromagnetic Phenomena
NOAA Chemical Sciences Laboratory
2007-2025
Cooperative Institute for Research in Environmental Sciences
2015-2024
University of Colorado Boulder
2015-2024
National Oceanic and Atmospheric Administration
2002-2022
NOAA Earth System Research Laboratory
2011-2020
EVRAZ (United Kingdom)
2018-2019
Institute for Health Metrics and Evaluation
2018
University of Virginia
1998-2002
University of Michigan–Ann Arbor
2001
University of Washington
2001
Abstract. We present and discuss a new dataset of gridded emissions covering the historical period (1850–2000) in decadal increments at horizontal resolution 0.5° latitude longitude. The primary purpose this inventory is to provide consistent reactive gases aerosols for use chemistry model simulations needed by climate models Climate Model Intercomparison Program #5 (CMIP5) support Intergovernmental Panel on Change (IPCC) Fifth Assessment report (AR5). Our best estimate year 2000 represents...
Abstract. Ozone holds a certain fascination in atmospheric science. It is ubiquitous the atmosphere, central to tropospheric oxidation chemistry, yet harmful human and ecosystem health as well being an important greenhouse gas. not emitted into atmosphere but byproduct of very chemistry it largely initiates. Much effort focused on reduction surface levels ozone owing its vegetation impacts, recent efforts achieve reductions exposure at country scale have proved difficult increases background...
The nationwide extent of surface ozone pollution in China and its comparison to the global distribution have not been recognized because scarcity Chinese monitoring sites before 2012. Here we address this issue by using latest 5 year (2013–2017) measurements from network, combined with recent Tropospheric Ozone Assessment Report (TOAR) database for other industrialized regions such as Japan, South Korea, Europe, United States (JKEU). We use various human health vegetation exposure metrics....
Abstract Tropospheric ozone plays a major role in Earth’s atmospheric chemistry processes and also acts as an air pollutant greenhouse gas. Due to its short lifetime, dependence on sunlight precursor emissions from natural anthropogenic sources, tropospheric ozone’s abundance is highly variable space time seasonal, interannual decadal time-scales. Recent, sometimes rapid, changes observed mixing ratios inspired us produce this up-to-date overview of global distribution trends. Much the text...
The Tropospheric Ozone Assessment Report (TOAR) is an activity of the International Global Atmospheric Chemistry Project. This paper a component report, focusing on present-day distribution and trends tropospheric ozone relevant to climate global atmospheric chemistry model evaluation. Utilizing TOAR surface database, several figures present daytime average at 2702 non-urban monitoring sites, highlighting regions seasons world with greatest levels. Similarly, ozonesonde commercial aircraft...
This Tropospheric Ozone Assessment Report (TOAR) on the current state of knowledge ozone metrics relevance to vegetation (TOAR-Vegetation) reports present-day global distribution at over 3300 vegetated sites and long-term trends nearly 1200 sites. TOAR-Vegetation focusses three vegetation-relevant time-periods across major world climatic zones: M12, mean during 08:00–19:59; AOT40, accumulation hourly values 40 ppb daylight hours, W126 with stronger weighting higher values, accumulated...
This study quantifies the present-day global and regional distributions (2010–2014) trends (2000–2014) for five ozone metrics relevant short-term long-term human exposure. These metrics, calculated by Tropospheric Ozone Assessment Report, are: 4th highest daily maximum 8-hour (4MDA8); number of days with MDA8 > 70 ppb (NDGT70), SOMO35 (annual Sum Means Over 35 ppb) two seasonally averaged (3MMDA1; AVGMDA8). were explored at monitoring sites worldwide, which classified as urban or...
This analysis provides an up‐to‐date assessment of long‐term (1990–2010) rural ozone trends using all available data in the western (12 sites) and eastern (41 USA. Rather than focus solely on average values or air quality standard violations, we consider full range values, reporting for 5th, 50th 95th percentiles. Domestic precursor emissions decreased strongly during 1990–2010. Accordingly 83%, 66% 20% summertime U.S. sites experienced statistically significant decreases 95th, 5th...
In support of the first Tropospheric Ozone Assessment Report (TOAR) a relational database global surface ozone observations has been developed and populated with hourly measurement data enhanced metadata. A comprehensive suite products including standard statistics, health vegetation impact metrics, trend information, are made available through common portal web interface. These form basis TOAR analyses focusing on human health, vegetation, climate relevant issues, which part this special...
The published literature debates the extent to which naturally occurring stratospheric ozone intrusions reach surface and contribute exceedances of U.S. National Ambient Air Quality Standard (NAAQS) for ground‐level (75 ppbv implemented in 2008). Analysis ozonesondes, lidar, measurements over western from April June 2010 show that a global high‐resolution (∼50 × 50 km 2 ) chemistry‐climate model (GFDL AM3) captures observed layered features sharp gradients deep intrusions, representing major...
From the earliest observations of ozone in lower atmosphere 19th century, both measurement methods and portion globe observed have evolved changed. These different uncertainties biases, data records differ with respect to coverage (space time), information content, representativeness. In this study, various datasets are reviewed selected for inclusion historical record background levels, based on relationship technique modern UV absorption standard, absence interfering pollutants,...
Abstract. We present an overview of the background, scientific goals, and execution Aerosol, Radiation, Cloud Processes affecting Arctic Climate (ARCPAC) project April 2008. then summarize airborne measurements, made in troposphere Alaskan Arctic, aerosol particle size distributions, composition, optical properties discuss sources transport aerosols. The data were grouped into four categories based on gas-phase composition. First, background contained a relatively diffuse, sulfate-rich...
Many prior studies clearly document episodic Asian pollution in the western U.S. free troposphere. Here, we examine mechanisms involved transport of plumes into surface air through an integrated analysis situ and satellite measurements May–June 2010 with a new global high‐resolution (∼50 × 50 km 2 ) chemistry‐climate model (GFDL AM3). We find that AM3 full stratosphere‐troposphere chemistry nudged to reanalysis winds successfully reproduces observed sharp ozone gradients above California,...
Abstract. Changes in baseline (here understood as representative of continental to hemispheric scales) tropospheric O3 concentrations that have occurred at northern mid-latitudes over the past six decades are quantified from available measurement records with goal providing benchmarks which retrospective model calculations global distribution can be compared. Eleven data sets (ten ground-based and one airborne) including European (beginning 1950's before), three North American 1984) two...
Abstract The California Research at the Nexus of Air Quality and Climate Change (CalNex) field study was conducted throughout in May, June, July 2010. organized to address issues simultaneously relevant atmospheric pollution climate change, including (1) emission inventory assessment, (2) transport dispersion, (3) chemical processing, (4) cloud‐aerosol interactions aerosol radiative effects. Measurements from networks ground sites, a research ship, tall towers, balloon‐borne ozonesondes,...
Surface ozone is a greenhouse gas and pollutant detrimental to human health crop ecosystem productivity. The Tropospheric Ozone Assessment Report (TOAR) designed provide the research community with an up-to-date observation-based overview of tropospheric ozone’s global distribution trends. TOAR Database contains metrics at thousands monitoring sites around world, densely clustered across mid-latitude North America, western Europe East Asia. Calculating regional trends these locations...
Abstract Two recent papers have quantified long‐term ozone (O 3 ) changes observed at northern midlatitude sites that are believed to represent baseline (here understood as representative of continental hemispheric scales) conditions. Three chemistry‐climate models (NCAR CAM‐chem, GFDL‐CM3, and GISS‐E2‐R) calculated retrospective tropospheric O concentrations part the Atmospheric Chemistry Climate Model Intercomparison Project Coupled Phase 5 model intercomparisons. We present an approach...
Abstract. Tropospheric ozone (O3) is a trace gas playing important roles in atmospheric chemistry, air quality and climate change. In contrast to North America Europe, long-term measurements of surface O3 are very limited China. We compile available observations at Mt. Tai – the highest mountain over China Plain during 2003–2015 analyze decadal change its sources. A linear regression analysis shows that summertime measured has increased significantly by 1.7 ppbv yr−1 for June 2.1 July–August...
Our understanding of the processes that control burden and budget tropospheric ozone has changed dramatically over last 60 years. Models are key tools used to understand these changes, underscore there many important in controlling budget. In this critical review, we assess our evolving processes, both physical chemical. We review model simulations from International Global Atmospheric Chemistry Climate Model Intercomparison Project Modelling Initiative changes its 1850 2010. Analysis data...
Recent aircraft observations show that tropospheric ozone increased above many Northern Hemisphere regions since the mid-1990s.
Ozone (O3) is a key air pollutant that produced from precursor emissions and has adverse impacts on human health ecosystems. In the U.S., Clean Air Act (CAA) regulates O3 levels to protect public welfare, but unraveling origins of surface complicated by presence contributions multiple sources including background like stratospheric transport, wildfies, biogenic precursors, international anthropogenic pollution, in addition U.S. sources. this report, we consider more than 100 published...