Methane emissions from northern lakes under climate change: a review

Abstract

AbstractNorthern lakes are important sources of CH4 in the atmosphere under the background of permafrost thaw and winter warming. We synthesize studies on thermokarst lakes, including various carbon sources for CH4 emission and the influence of thermokarst drainage on carbon emission, to show the evasion potential of ancient carbon that stored in the permafrost and CH4 emission dynamics along with thermokarst lake evolution. Besides, we discuss the lake CH4 dynamics in seasonally ice-covered lakes, especially for under-ice CH4 accumulation and emission during spring ice melt and the possible influential factors for CH4 emission in ice-melt period. We summarize the latest findings and point out that further research should be conducted to investigate the possibility of abundant ancient carbon emission from thermokarst lakes under climate warming and quantify the contribution of ice-melt CH4 emission from northern lakes on a large scale.