Long-Term Monitoring of Methane within New York State Phase II: Assessing Trends in Sources and Characterizing Hot Spots

DESCRIPTION: CH4 is the most abundant volatile organic compound in the atmosphere, with an atmospheric lifetime of ~9 years and a global warming potential ~30 times greater than carbon dioxide (CO2) over 100-year time horizons. It is a major precursor for the production of tropospheric ozone, a criteria pollutant under the US National Ambient Air Quality Standards (NAAQS) and also a potent GHG. Meanwhile, nitrous oxide (N2O) is the most abundant fixed-nitrogen gas species, with an atmospheric lifetime of ~116 years and a global warming potential ~280 times greater than CO2 over 100-year time horizons. Despite this, both CH4 and N2O long remained unregulated, and atmospheric abundances have respectively increased by 300% and 20% since the Industrial Revolution, about half of the net anthropogenic forcing over this period. In 2015, NYS committed to 40% reductions in its GHG emissions by 2030 relative to 1990 in its Reforming the Energy Vision (REV) goals. In May 2017, NYS announced that in order to meet these goals, it would specifically target in-state CH4 emissions as outlined in its Methane Reduction Plan (MRP), citing a relatively rapid climate response and co-benefits on surface air quality. To date, N2O targets have not been announced, although these would also experience a more rapid climate response than CO2 and would have co-benefits on stratospheric ozone recovery rates. A detailed understanding of regional CH4 budgets is critical for adopting successful policies for reducing emissions, but these remain highly uncertain due to large co-location and overlap of natural (primarily wetlands) and anthropogenic (primarily natural gas extraction and distribution, cows, and landfills). In this project, we will measure methane, ethane, N2O, CO2 and CO from towers and on mobile campaigns through different seasons.