NH3 Atmosphere-Surface Exchange
We found there are 25 National Parks within 100 miles of an agricultural hotspot range using satellite NH3 observations. Transported NH3 could significantly impact nitrogen balance and ecosystem health of these parks. Despite the importance of NH3 dry deposition, NH3 flux has rarely been measured directly in the US, partly due to the complex bidirectional nature of NH3 atmosphere-surface exchange. Through my Ph.D. and postdoctoral work, we measured and modeled NH3 fluxes in Rocky Mountain National Park. Using backward-trajectory analysis, we linked high deposition to agricultural plumes transported to the Park.
CH4 Emissions from Natural Gas Vehicles in China
The population of natural gas vehicles (NGVs) in China increased from 6000 to 6 million from 2000 to 2017, but their CH4 emissions had been overlooked. Using a mobile measurement technique that collected large numbers of samples, we showed that CH4 emissions from NGVs in China were much higher than previous estimates. With policy scenarios and life-cycle analyses, we highlighted the importance of emission standard enforcement, which could lead to a GHG reduction equivalent to eliminating emissions of 12 million passenger cars in China.
VOCs at Carlsbad Caverns National Park (CAVE)
CAVE located in southeastern New Mexico, experiences elevated ground-level ozone (O3) exceeding the National Ambient Air Quality Standard (NAAQS) of 70 ppbv. It is situated adjacent to the Permian Basin, one of the largest oil and gas (O&G) producing regions in the US. Using positive matrix factorization (PMF) analysis of speciated VOCs, we characterized VOC sources and confirmed the impacts of O&G activities on VOC observed at CAVE.
Read more about VOC source attribution.
Read more about O3 precursors.
Read more about impacts of oil and gas on O3.
