Spatial Context of Landfill CH4 and CO2 Emission Captured By the Eddy Covariance Tower.

Methane and carbon dioxide emissions were continuously measured by the eddy covariance method from June to December 2010 at the municipal landfill in Lincoln, NE. Methane concentrations varied strikingly from near background to more than 60 ppm. Methane emission rates varied as much as 35-fold from day to day and depended strongly on changes in barometric pressure and wind directions at the site. We use continuous two-dimensional footprint modeling to investigate the spatial and temporal variations of CH₄ and CO₂ emission in the context of vent locations. Our results for estimating CH₄ and CO₂ emission rates and their variations will be discussed in terms of power spectrum, ogive analysis, and footprint modeling.