A5010800133- Atmospheric chemistry and aerosols
- Air Quality and Health Impacts
- Atmospheric and Environmental Gas Dynamics
- Vehicle emissions and performance
- Atmospheric Ozone and Climate
- Mercury impact and mitigation studies
- Toxic Organic Pollutants Impact
- Air Quality Monitoring and Forecasting
- Atmospheric aerosols and clouds
- Odor and Emission Control Technologies
- Wind and Air Flow Studies
- Meteorological Phenomena and Simulations
- Industrial Gas Emission Control
- Global Energy and Sustainability Research
- Chemical and Physical Properties in Aqueous Solutions
- Metal Extraction and Bioleaching
- Climate variability and models
- Minerals Flotation and Separation Techniques
- Land Use and Ecosystem Services
- Satellite Image Processing and Photogrammetry
- Advanced Chemical Sensor Technologies
- Energy, Environment, and Transportation Policies
- nanoparticles nucleation surface interactions
- Catalytic Processes in Materials Science
- Water Quality Monitoring and Analysis
ENVIRON (United States)
2010-2025
Ramboll (United Kingdom)
2025
Marin Community Foundation
2020
Atmospheric and Environmental Research
2000-2011
L-3 Communications (United States)
2000
University of Kentucky
1983-1987
A multiscale modeling system that consists of a global chemical transport model (CTM) and nested continental CTM was used to simulate the atmospheric fate mercury its deposition over contiguous United States. The performance CTMs evaluated against available data. coefficient determination (r2) for observed versus simulated annual wet fluxes North America 0.50 with average normalized error bias 25% 11%, respectively. were conduct source attribution selected receptor areas. Three emission...
A numerical simulation of the atmospheric fate and transport mercury (Hg) was conducted using a multiscale approach. Two different spatial scales were used to simulate (1) global cycling Hg (2) deposition in potentially sensitive areas. The an updated version our chemical model (CTM). imbedded continental regional/continental CTM, TEAM. Simulations 1998 meteorology 1998/1999 emission inventories. Model results show improved performance compared earlier simulations. For example, shows...
A unified model framework with online‐coupled meteorology and chemistry consistent treatments across spatial scales is required to realistically simulate chemistry‐aerosol‐cloud‐radiation‐precipitation‐climate interactions. In this work, a global‐through‐urban WRF/Chem (i.e., GU‐WRF/Chem) has been developed provide such these important interactions wide range of while reducing uncertainties from the use offline‐coupled systems inconsistent treatments. Evaluation against available...
Abstract. Source apportionment modeling provides valuable information on the contributions of different source sectors and/or regions to ozone (O3) or fine particulate matter (PM2.5) concentrations. This can be useful in designing air quality management strategies and understanding potential benefits reducing emissions from a particular category. The Comprehensive Air Model with Extensions (CAMx) offers unique attribution tools, called Ozone Particulate Apportionment Technology (OSAT/PSAT),...
This paper describes the application of a photochemical puff model to simulate near-source impacts air emissions associated with amine-based post-combustion CO2 capture. Amines react in atmosphere hydroxyl (OH) radical and other oxidants form potentially harmful products, such as nitrosamines nitramines. can also particles sulfuric acid that may be present amine absorber or atmosphere. Nitrosamines photolyze back amino radical. Simulating these processes requires use provide concentrations...
We describe the development, evaluation, and application of a new plume‐in‐grid model for investigating subgrid‐scale effects, associated with NO x emissions from large elevated point sources, on O 3 formation. Traditional Eulerian air quality models cannot resolve strong concentration gradients created by plumes emitted sources. Although several approaches have been used in past to address this issue, they limited their simplistic simulation plume dispersion and/or chemistry lack treatment...
Multi-pollutant chemical transport models (CTMs) are being routinely used to predict the impacts of emission controls on concentrations and deposition primary secondary pollutants. While these have a fairly comprehensive treatment governing atmospheric processes, they unable correctly represent processes that occur at very fine scales, such as near-source chemistry emissions from elevated point sources, because their relatively coarse horizontal resolution. Several different approaches been...
An existing plume‐in‐grid model for ozone and particulate matter, which provides an explicit treatment of stack plumes embedded within a three‐dimensional grid‐based Eulerian air quality model, is extended to include comprehensive mercury (Hg) processes. The applied the continental United States investigate subgrid‐scale effects associated with Hg emissions from large elevated point sources on atmospheric concentrations deposition. top thirty Hg‐emitting power plants in U.S. were selected...
To achieve the current United States National Ambient Air Quality Standards (NAAQS) attainment level for ozone or particulate matter, photochemical air quality models include tools to determine source apportionment and/or sensitivity. Previous studies by authors have used Ozone and Particulate Matter Source Apportionment Technology Higher-order Decoupled Direct Method probing in CAMx investigate these source-receptor relationships ozone. The recently available CMAQ, referred as Integrated...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSource-receptor relationships. A look at acid deposition modelingAkula. Venkatram and Prakash. KaramchandaniCite this: Environ. Sci. Technol. 1986, 20, 11, 1084–1091Publication Date (Print):November 1, 1986Publication History Published online1 May 2002Published inissue 1 November 1986https://pubs.acs.org/doi/10.1021/es00153a002https://doi.org/10.1021/es00153a002research-articleACS PublicationsRequest reuse permissionsArticle...
We describe the development and evaluation of a new reactive plume model that combines state-of-the-science puff with an optimized chemistry accurately represents power plant at various stages its evolution. The uses second-order closure scheme, allowing for accurate treatment dispersion influence turbulent concentration fluctuations on chemical rates. was tested using helicopter measurements from 1995 Southern Oxidants Study (SOS) Nashville/Middle Tennessee Ozone Study. applied 6 days in...
The interactions between climate and air quality are receiving increasing attention due to their high relevancy change. Coupled models being developed study these interactions. These need address the transport chemistry of atmospheric species over a large range scales conditions. In particular, mechanism is key component such because it needs include relevant reactions simulate lower troposphere, upper stratosphere, as well polluted, rural, clean, marine environments. This paper describes...
Coal‐fired electric power plants produce a large fraction of total U.S. NO x emissions, but from this sector has been declining in the last decade owing to installation control technology. Nighttime aircraft intercepts plumes two different Texas (Oklaunion near Wichita Falls and W. A. Parish Houston) with technologies demonstrate effect these reductions on nighttime oxidation rates. The analysis shows that spatial extent nighttime‐emitted be quite limited mixing highly concentrated plume...
The SCICHEM model incorporates complete gas phase, aqueous and aerosol phase chemistry within a state-of-the-science Gaussian puff SCIPUFF (Second-order Closure Integrated Puff). is valuable tool that can be used to calculate the impacts of single source or small number sources on downwind ozone PM2.5. has flexible data requirements: it run with routine surface upper air observations prognostic meteorological outputs emissions are specified in simple text format. This paper describes...
Three modeling approaches, the U.S. Environmental Protection Agency's (EPA) Community Multiscale Air Quality (CMAQ) zero-out, Comprehensive quality Model with extensions (CAMx) and CAMx probing tools ozone source apportionment tool (OSAT), were used to project contributions of various categories future year design values for summer 8-hr average concentrations at selected monitors. The CMAQ zero-out or brute-force approaches predicted generally similar most categories, some small differences....
The subgrid-scale simulation of plume chemistry in three-dimensional air quality models can be computationally demanding. To minimize this computational burden, a reduced kinetic mechanism for the gas-phase power plant plumes is developed and validated against full chemical mechanism. This simulates according to three stages evolution: (1) A first stage where radical concentrations are negligible limited four major reactions during day two at night. (2) second OH NO3 radicals sufficiently...