Methane (CH4) is one of the major greenhouse gases with a CO2relative global warming potential above 20 over a 100-year period (IPCC TAR). Global average concentration of this tracer in Earth's atmosphere is increasing due to widely spread surface sources of both anthropogenic and biogenic origins. To better understand highly variable in space and time surface-atmosphere exchange fluxes of CH4 and to quantify them within meaningful range of uncertainties, continuous long-term in situ observations of atmospheric concentrations from dense sites are required. Last year Earth Networks began the deployment of 100 cavity ring- down spectrometers to continuously measure CO2 and CH4. Currently, 20 instruments are fully deployed in the U.S., and many of the sites are in the northeast and around the Marcellus Shale formation. High sampling rate and the density of the sites in the region, which have diverse GHG sources, complex terrain and dynamic weather patterns, are important source of information to resolve multi-scale processes both at the surface and in the atmosphere. In this study the dense network measurements are analyzed for each site and for the entire region to evaluate the variability of atmospheric GHG levels and to identify their sources. We discuss our findings and results based on inverse modeling using the WRF-STILT system and the GHG observations from the recently deployed network in the northeastern U.S. network.
Proceedings Title: Proceedings of the 4th NACP All-Investigators Meeting
Conference Dates: February 4-7, 2013
Conference Location: Albuquerque, NM
Conference Title: 4th NACP All-Investigators Meeting
Pub Type: Conferences
Greenhouse gas measurements, Inversion modeling