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Abstract Phase One of the Transportation and Transformation of Ammonia (TRANS2Am) field campaign took place in northeastern Colorado during the summer of 2021. One of the goals of TRANS2Am was to measure ammonia (NH3) emissions from cattle feedlots and dairies. Most of these animal husbandry facilities are co‐located within oil and gas development, an important source of methane (CH4) and ethane (C2H6) in the region. Phase One of TRANS2Am included 12 near‐source research flights. We present estimates of NH3emissions ratios with respect to CH4(NH3EmR), with and without correction of CH4from oil and gas, for 29 feedlots and dairies in the region. The data shows larger emissions ratios than previously reported in the literature with a large range of values (i.e., 0.1–2.6 ppbv ppbv−1). Facilities housing cattle and dairy had a mean (std) of 1.20 (0.63) and 0.29 (0.08) ppbv ppbv−1, respectively. We also found that only 15% of the total ammonia (NHx) is in the particle phase (i.e., ) near major sources during the warm summertime months. We examined the evolution of NH3in one plume that was sampled at different distances and altitudes up to 25 km downwind and estimated the NH3lifetime against deposition and partitioning to the particle phase to be 87–120 min. Finally, we calculated estimates of NH3emission rates from four optimally sampled facilities. These ranged from 4 to 29 g NH3 · h−1 · hd−1.
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Initial Cost Barrier of Ammonia Control in Central China
Abstract Ammonia control has received increasing attention as a measure to decrease particulate concentrations. Modeling analysis of observation data from central China over the period of September 2015 to August 2016 shows clear asymmetric responses of particulate pH and mass to ammonia emissions. With a change of ±80% of NHx(NH3+ NH4+), the corresponding ΔpH are +0.5 and −3.0, respectively, and the corresponding particulate NH4+changes are +2.62% and −61.8%, respectively. This asymmetry implies that there is a Critical Total Ammonia Concentration, above which particulate pH and mass are insensitive to ammonia control. Analysis of the observation data suggests that the Critical Total Ammonia Concentration is −25%. The estimated cost for an NHxreduction of 25% is $140 – 320 million for Hubei province, which is the initial cost barrier before ammonia control can effectively affect particulate pH and mass in central China. This cost barrier will increase as NOxand SO2emissions decrease.
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- Award ID(s):
- 1743401
- PAR ID:
- 10457225
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Geophysical Research Letters
- Volume:
- 46
- Issue:
- 23
- ISSN:
- 0094-8276
- Page Range / eLocation ID:
- p. 14175-14184
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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