We found a match
Your institution may have rights to this item. Sign in to continue.
- Title
Aircraft-based inversions quantify the importance of wetlands and livestock for Upper Midwest methane emissions.
- Authors
Yu, Xueying; B. Millet, Dylan; C. Wells, Kelley; K. Henze, Daven; Cao, Hansen; J. Griffis, Timothy; A. Kort, Eric; Plant, Genevieve; J. Deventer, Malte; K. Kolka, Randall; Tyler Roman, D.; J. Davis, Kenneth; R. Desai, Ankur; C. Baier, Bianca; McKain, Kathryn; C. Czarnetzki, Alan; Anthony Bloom, A.
- Abstract
We apply airborne measurements across three seasons (summer, winter, spring 2017-2018) in a multi-inversion framework to quantify methane emissions from the US Corn Belt and Upper Midwest, a key agricultural and wetland source region. Combing our seasonal results with prior fall values we find that wetlands are the largest regional methane source (32%,20[16-23]Gg/d), while livestock (enteric/manure; 25%, 15[14-17]Gg/d) are the largest anthropogenic source. Natural gas/petroleum, waste/landfills, and coal mines collectively make up the remainder. Optimized fluxes improve model agreement with independent datasets within and beyond the study timeframe. Inversions reveal coherent and seasonally dependent spatial errors in the WetCHARTs ensemble mean wetland emissions, with an underestimate for the Prairie Pothole region but an overestimate for Great Lakes coastal wetlands. Wetland extent and emission temperature dependence have the largest influence on prediction accuracy; better representation of coupled soil temperature-hydrology effects is therefore needed. Our optimized regional livestock emissions agree well with Gridded EPA estimates during spring (to within 7%), but are ~25% higher during summer/winter. Spatial analysis further shows goodtop-down/bottom-up agreement for beef facilities, but larger (~30%) seasonal discrepancies for dairies and hog farms. Findings thus support bottom-up enteric emission estimates but suggest errors for manure; we propose that the latter reflects inadequate treatment of management factors including field application. Overall, our results confirm the importance of intensive animal agriculture for regional methane emissions, implying substantial mitigation opportunities through improved management.
- Subjects
ATMOSPHERIC methane; COASTAL wetlands; METHANE; WETLANDS; NATURAL gas; LIVESTOCK; AGRICULTURAL intensification; WETLAND soils
- Publication
Atmospheric Chemistry & Physics Discussions, 2020, p1
- ISSN
1680-7367
- Publication type
Article
- DOI
10.5194/acp-2020-826