A5074169558- Atmospheric chemistry and aerosols
- Atmospheric and Environmental Gas Dynamics
- Plant responses to elevated CO2
- Atmospheric Ozone and Climate
- Plant Water Relations and Carbon Dynamics
- Air Quality Monitoring and Forecasting
- Atmospheric aerosols and clouds
- Air Quality and Health Impacts
- Wind and Air Flow Studies
- Aerospace Engineering and Energy Systems
- Climate change and permafrost
- Urban Heat Island Mitigation
- Meteorological Phenomena and Simulations
- Climate variability and models
- Cryospheric studies and observations
- Plant and animal studies
- Vehicle emissions and performance
- Building Energy and Comfort Optimization
- Plant biochemistry and biosynthesis
- Indoor Air Quality and Microbial Exposure
- Hydrocarbon exploration and reservoir analysis
- Environmental Education and Sustainability
- Remote Sensing in Agriculture
- Adventure Sports and Sensation Seeking
- Experimental and Theoretical Physics Studies
DePaul University
2013-2024
Belden (United States)
2013-2022
Desert Research Institute
2006-2009
NSF National Center for Atmospheric Research
2003-2008
Institute of Arctic and Alpine Research
2008
Japan Petroleum Energy Center
2008
University of Colorado Boulder
2008
Tokyo Metropolitan University
2008
Lamont-Doherty Earth Observatory
1999-2005
Columbia University
1999-2005
<strong class="journal-contentHeaderColor">Abstract.</strong> The global emissions of isoprene are calculated at 0.5° resolution for each year between 1995 and 2006, based on the MEGAN (Model Emissions Gases Aerosols from Nature) version 2 model (Guenther et al., 2006) a detailed multi-layer canopy environment calculation leaf temperature visible radiation fluxes. is driven by meteorological fields – air temperature, cloud cover, downward solar irradiance, windspeed, volumetric...
Disjunct eddy covariance in conjunction with continuous in‐canopy gradient measurements allowed for the first time to quantify fine‐scale source and sink distribution of some most abundant biogenic (isoprene, monoterpenes, methanol, acetaldehyde, acetone) photooxidized (MVK+MAC, acetone, acetic, formic acid) VOCs an old growth tropical rain forest. Our revealed substantial isoprene emissions (up 2.50 mg m −2 h −1 ) light‐dependent monoterpene 0.33 at peak dry season (April May 2003)....
Airborne and ground‐based mixing ratio flux measurements using eddy covariance (EC) for the first time mixed layer gradient (MLG) variance (MLV) techniques are used to assess impact of isoprene monoterpene emissions on atmospheric chemistry in Amazon basin. Average noon (7.8 ± 2.3 mg/m 2 /h) fluxes (1.2 0.5 compared well between ground airborne higher than estimated this region during other seasons. The biogenic emission model, Model Emissions Gases Aerosols from Nature (MEGAN), estimates...
Biogenic volatile organic compounds (BVOC) contribute significantly to the formation of ozone and secondary aerosol (SOA). The Model Emissions Gases Aerosols from Nature (MEGANv2.02) is used estimate emissions isoprene, monoterpenes (MT), sesquiterpenes (SQT) across United States. Compared Emission Inventory System (BEIS3.0), MEGANv2.02 estimates higher isoprene but lower MT for July 2001 January 2002. A sensitivity study SQT emission factors algorithm parameters was conducted by assigning...
Abstract. We have incorporated a semi-mechanistic isoprene emission module into the JULES land-surface scheme, as first step towards modelling tool that can be applied for studies of vegetation – atmospheric chemistry interactions, including chemistry-climate feedbacks. Here, we evaluate coupled model against local above-canopy flux measurements from six tower sites well satellite-derived estimates over tropical South America and east south Asia. The simulates diurnal variability well:...
Ozone (O3) pollution threatens global public health and damages ecosystem productivity. Droughts modulate surface O3 through meteorological processes vegetation feedbacks. Unraveling these influences is difficult with traditional chemical transport models. Here, using an atmospheric chemistry–vegetation coupled model in combination a suite of existing measurements, we investigate the drought impacts on explore main driving processes. Relative to mean state, accelerated photochemical rates...
A one‐dimensional canopy model was used to quantify the impact of photochemistry in modifying biosphere‐atmosphere exchange trace gases. Canopy escape efficiencies, defined as fraction emission that escapes into well‐mixed boundary layer, were calculated for reactive terpene species. The modeled processes emission, photochemistry, diffusive transport, and deposition highly constrained based on intensive observations collected a Loblolly Pine plantation at Duke Forest, North Carolina, during...
Abstract. We describe the implementation of a biochemical model isoprene emission that depends on electron requirement for synthesis into Farquhar–Ball–Berry leaf photosynthesis and stomatal conductance is embedded within global chemistry-climate simulation framework. The production calculated as function transport-limited photosynthesis, intercellular atmospheric carbon dioxide concentration, canopy temperature. vegetation biophysics module computes photosynthetic uptake coupled with...
Abstract The interaction of global climate change and urban heat islands (UHI) is expected to have far-reaching impacts on the sustainability world’s rapidly growing population centers. Given that a wide range spatiotemporal scales contributed by meteorological forcing complex surface heterogeneity complicates UHI, multimodel nested approach used in this paper study climate-change Chicago, Illinois, covering relevant scales. One-way dynamical downscaling with model chain consisting...
Abstract. Whole-system fluxes of isoprene from a moist acidic tundra ecosystem and leaf-level emission rates common species (Salix pulchra) in that same were measured during three separate field campaigns. The campaigns conducted the summers 2005, 2010 2011 took place at Toolik Field Station (68.6° N, 149.6° W) on north slope Brooks Range Alaska, USA. maximum rate whole-system flux was over 1.2 mg C m−2 h−1 with an air temperature 22 °C PAR level 1500 μmol s−1. Leaf-level for S. pulchra...
Hourly data for concentrations and fluxes of CO 2 at 30 m in Harvard Forest (Petersham, Massachusetts) are analyzed using linear modeling to obtain regionally representative a continental site. The time series is decomposed into contributions due regional combustion, local canopy exchange, monthly average biotic exchange (as modulated by the daily cycle growth decay planetary boundary layer (PBL)), background concentration. Attributions derived analysis, tracer combustion (CO or acetylene (C...
Biogenic volatile organic compounds (BVOCs), primarily emitted by terrestrial vegetation, are highly reactive and have large effects on the oxidizing potential of troposphere, air quality climate. In terms global emissions, isoprene is most important BVOC. Droughts bring about changes in surface emission biogenic hydrocarbons mainly because plants suffer water stress. Past studies report that current parameterization state-of-the-art Model Emissions Gases Aerosols from Nature (MEGAN) v2.1,...
Two cottonwood plantations were grown at different CO2 concentrations the Biosphere 2 Laboratory in Arizona to investigate response of isoprene emission elevated [CO2] and its interaction with water deficits. We focused on responses due seasonal variation mean climate from one year next. In fall spring, rate showed a similar inhibition by [CO2], despite an 8–10°C difference air temperature. The overall drought was also for observations conducted during spring or fall, two years approximate...
Abstract. Biogenic volatile organic compounds (BVOC) produced by plants are known to have an important role in atmospheric chemistry. However, our knowledge of the range BVOCs different plant processes is still expanding, and there remain poorly understood categories BVOCs. In this study, emissions a novel class BVOC were investigated desert region. Our study considered 8 species common plants: blackbrush (Coleogyne ramosissima), willow (Chilopsis linearis), mesquite (Prosopis glandulosa),...
Continuous time‐series estimates of net ecosystem carbon exchange (NEE) are routinely made using eddy covariance techniques. Identifying and compensating for errors in the NEE time series can be automated a signal processing filter like ensemble Kalman (EnKF). The EnKF compares each measurement to model prediction updates estimate by weighting relative specified error an model‐prediction that is continuously updated based on predictions earlier measurements series. Because among variables,...
Abstract Stress‐induced emissions of biogenic volatile organic compounds (VOCs) from terrestrial ecosystems may be one the dominant sources VOC worldwide. Understanding ecosystem stress response could reveal how will respond and adapt to climate change and, in turn, quantify changes atmospheric burden oxidants secondary aerosols. Here, we argue, based on preliminary evidence several opportunistic measurement sources, that chemical signatures can identified quantified at scale. We also...