A CH4 emission estimate for the Kuparuk River basin, Alaska

Integrated annual methane fluxes measured from 1994 to 1996 at sites representing specific tundra vegetation and land cover types were weighted areally using a vegetation map [Auerbach ef al., 1997] for the Kuparuk River basin and subareas. Wetland and open water CH4 emissions dominate the Kuparuk River basin emission estimate. Areal weighting of site fluxes resulted in a regional CH4 emission estimate of 2.09 x 10(10) g CH4 yr(-1) for the Kuparuk River basin. The global CH4 emission obtained by extending areally weighted annual fluxes from this study to global tundra area (7.34 x 10(12) m(2)) is 5.83 Tg CH4 yr(-1). This is about 15% of the Fung et al. [1991] atmospheric tracer model estimate and indicates that the vegetation distribution of the Kuparuk River Basin is not typical of the entire Arctic. Reconciling results from atmospheric tracer model estimates and areally weighted field flux measurements will require accurate high-resolution circumpolar estimates of wetland and open water areas and fluxes.