A5029346436- Atmospheric chemistry and aerosols
- Atmospheric and Environmental Gas Dynamics
- Atmospheric Ozone and Climate
- Atmospheric aerosols and clouds
- Air Quality Monitoring and Forecasting
- Methane Hydrates and Related Phenomena
- Hydrocarbon exploration and reservoir analysis
- Aeolian processes and effects
- Underwater Vehicles and Communication Systems
- Meteorological Phenomena and Simulations
- Opportunistic and Delay-Tolerant Networks
- Fire effects on ecosystems
- Air Quality and Health Impacts
- Satellite Communication Systems
Crestone (United States)
2022-2023
Lake County
2022
Colorado Department of Public Health and Environment
1995-2017
NSF National Center for Atmospheric Research
2016-2017
Atmospheric Chemistry Observations & Modeling
2016
Ames Research Center
2013
Spectral aerosol optical depth, τ a , observed at Mauna Loa, Hawaii, for the past 11 years is analyzed background variations and effects of two major volcanic eruptions: El Chichón in 1982 Mount Pinatubo 1991. A previously known annual variation near‐background levels are present record. The data high accuracy, being primarily obtained from an automatic precision sunphotometer reduced using Langley‐plot slope method. values over Loa were greater immediately after eruption than due to more...
Abstract We use daily maximum 8 h average surface O 3 concentrations (MDA8) for July 1995–2013, meteorological variables from the National Center Environmental Prediction/National Atmospheric Research Reanalysis, North American Regional and output regional chemistry‐climate simulations to assess relationships between weather in western U.S. also explore among , satellite‐derived NO 2 meteorology. A primary objective of this study is identify an effective method correcting effects meteorology...
Abstract. Stratosphere-to-troposphere transport (STT) results in air masses of stratospheric origin intruding into the free troposphere. Once troposphere, ozone (O3)-rich can be transported and mixed with tropospheric masses, contributing to O3 budget. Evidence STT identified based on differences trace gas composition two regions. Because is present such large quantities stratosphere compared it frequently used as a tracer for events. This work reports airborne situ measurements other gases...
A high-ozone (O3) pollution episode was observed on 22 July 2014 during the concurrent "Deriving Information Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality" (DISCOVER-AQ) "Front Range Pollution Photochemistry Experiment" (FRAPPE) campaigns in northern Colorado. O3 monitors at three regulatory sites exceeded Environmental Protection Agency (EPA) 2008 National Ambient Quality Standard (NAAQS) daily maximum 8 h average (MDA8) of 75 ppbv. To further...
Abstract. We present airborne measurements made during the 2014 Front Range Air Pollution and Photochemistry Experiment (FRAPPÉ) project to investigate impacts of Denver Cyclone on regional air quality in greater area. Data trace gases, non-refractory submicron aerosol chemical constituents, optical extinction (βext) at λ = 632 nm were evaluated presence absence surface mesoscale circulation three distinct study regions Range: In-Flow, Northern Range, metropolitan Pronounced increases mass...
Abstract We describe the resources used, deployment strategy, and outcomes of Front Range Air Pollution Photochemistry Éxperiment (FRAPPÉ) experiment, which took place in summer 2014 Colorado. provide a history air quality region previously conducted experiments, atmospheric conditions encountered during campaign, summarize scientific findings that campaign produced, together with Deriving Information on Surface Conditions from Column Vertically Resolved Observations Relevant to Quality...
Abstract Transport is a key parameter in air quality research and plays dominant role the Colorado Northern Front Range Metropolitan Area (NFRMA), where terrain‐induced flows recirculation patterns can lead to vigorous mixing of different emission sources. To assess transport processes their connection NFRMA during FRAPPÉ DISCOVER‐AQ campaigns summer 2014, we use Weather Research Forecasting Model with inert tracers. Overall, model represents well measured winds, tracers are good agreement...
Aerosol optical depths and values for the Angstrom exponent, alpha, were retrieved from carefully calibrated sunphotometer measurements which made during Global Change Expedition (GCE) of NOAA ship Mt. Mitchell in July, August, September 1988. Sunphotometer observations acquired at wavelengths 380, 500, 675, 778 nm. Optical alphas have been segregated into five categories associated with probable air mass source regions determined through back trajectories 1000‐, 850‐, 700‐, 500‐mbar levels....
In 1990, the State of Colorado implemented a visibility standard 0.076 km−1 beta extinction for Denver metropolitan area. Meteorologists with Colorado's Air Pollution Control Division forecast high pollution days associated impairment as well those due to levels federal criteria pollutants. Visibility forecasts are made from few hours up about 26 h in advance period interest. Here we discuss key microscale, mesoscale, and synoptic-scale features episodes impairment. Data special studies,...
Abstract. We present airborne measurements made in the Colorado Front Range aboard NSF C-130 aircraft during 2014 Air Pollution and Photochemistry Éxperiment (FRAPPÉ) project. Data on trace gases, non-refractory sub-micron aerosol chemical constituents, optical extinction (βext) at λ = 632 nm presence absence of a surface mesoscale circulation pattern, called Denver Cyclone, were analyzed three study regions Range: In-Flow, Northern (NFR), Metropolitan (DM). Pronounced increases mass...
Abstract The oil and gas (O&G) sector is estimated to be the largest contributor anthropogenic methane (CH 4 ) emissions in Colorado. Since 2004, State of Colorado has implemented multiple regulations significantly reduce from O&G sector. Denver‐Julesburg Basin (DJ Basin) a significant producing region northern Colorado, production here steadily increased over last decade. To assess CH trends Northern we selected retrievals NASA Atmospheric Infrared Sounder (AIRS) instrument for...
Abstract. Stratosphere-to-troposphere transport (STT) results in air masses of stratospheric origin intruding into the free troposphere. Once troposphere, O3-rich can be transported and mixed with tropospheric masses, contributing to O3 budget. Evidence STT identified based on differences trace gas composition two regions. Because ozone (O3) is present such large quantities stratosphere compared it frequently used as a tracer for events. This work reports airborne situ measurements other...
Correlations between ozone and methane, ethane, oil gas emissions are high in the north lower south of study region.• Spatial gradients correlations trends maximum O3 match modeled contributions.• Regression Bayesian correlation suggest that 67% from O&G VOCs has been eliminated at northern sites 2012 2019.
Abstract The Denver Metro/Northern Front Range area has been designated a severe nonattainment (NAA) for O 3 . Previous research associated with the 2014 Air Pollution and Photochemistry Éxperiment field campaign 2017 source apportionment modeling analysis point to north‐south gradients in oil gas (O&G) impacts on , greater contributions north dominance of mobile sources south. Recent Atmospheric Infrared Sounder satellite methane enhancement ethane trends show ∼50% ∼70% reductions...
The oil and gas (O&G) sector is estimated to be the largest contributor anthropogenic methane (CH4) emissions in Colorado. Since 2004, State of Colorado has implemented multiple regulations significantly reduce from O&G sector. Denver-Julesburg Basin (DJ Basin) a significant producing region northern Colorado, production here steadily increased over last decade. To assess CH4 trends Northern we selected retrievals NASA Atmospheric Infrared Sounder (AIRS) instrument for 2003-2020. study grid...