Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5780589 | Polar Science | 2016 | 26 Pages |
Abstract
Dissolved methane concentrations (DM) in thirty lakes along Dalton Highway were measured in the open water season in 2008 and in 2012 to estimate diffusive flux from lake surfaces and to verify the enhancive effect of thawing permafrost on flux in the Alaskan arctic zone. An inverse relationship between lake size and DM was obtained in lakes in the regions as was found for European boreal lakes. There was no evidence indicating an effect of thawing permafrost on DM in these lakes. DM in lakes in the taiga region, however, were higher than those in the tundra region. All lake images on a map larger than 0.001 km2 were analyzed, and the area and number distributions were obtained in order to calculate regional mass fluxes of diffusive methane. The total area of all lakes (339,733) in the Alaskan Arctic zone (northern region from 64.00°N) is 25.5 Ã 103 km2. Regional summer diffusive flux of methane from lakes in the Alaskan arctic zone was estimated to be 22 Gg CH4 yrâ1. Average diffusive flux density (per lake area) was 0.86 g CH4 mâ2 yrâ1, which is similar to that in European boreal lakes.
Keywords
Related Topics
Physical Sciences and Engineering
Earth and Planetary Sciences
Earth and Planetary Sciences (General)
Authors
Masafumi Sasaki, Yong-Won Kim, Masao Uchida, Motoo Utsumi,