Doctoral Dissertation Research: Another piece of the Arctic carbon puzzle: quantifying emissions from Arctic lakes in drier regions

Lakes are a dominant feature of the Arctic landscape and can be important sources of carbon dioxide to the atmosphere, but large-scale Arctic carbon budgets usually neglect carbon emissions from lakes. Moreover, studies of carbon emissions from northern lakes have largely been limited to regions where lakes are connected to thawing permafrost. Emissions from lakes located in drier landscapes, which cover about 25% of the northern permafrost region, have been relatively understudied.

Consequently, it is uncertain to what degree lakes located in drier regions contribute to carbon emissions, a problem that likely will worsen as much of the Arctic is predicted to become warmer and drier in the future. This project addresses both critical gaps. First, the researchers are using automated sensors to measure carbon emissions from lakes in West Greenland, a region experiencing rapid warming and declining precipitation.

The researchers are also synthesizing their lake emission measurements with previously published observations to assess how differences in climate patterns impact fluxes of carbon dioxide between lakes and the atmosphere. The results of this research will be presented in interdisciplinary academic panels, popular science magazines, youth science programs, and discussed with West Greenland communities.

The Kangerlussuaq region in West Greenland located along a hydro-climatic gradient serves as a model landscape for studying the implications of warmer and drier Arctic conditions for carbon dynamics in inland waters. The researchers are quantifying carbon emissions from a suite of lakes along a climate-precipitation gradient that mimics shifts from cooler and wetter climate to drier and warmer conditions throughout the whole year, using high-frequency, in situ sensors.

These sensors are providing the first annual, temporally well resolved measurements of carbon dioxide emissions from lakes in poorly hydrologically connected, arid Arctic landscapes. The researchers are upscaling their measurements to the regional level and comparing them with terrestrial carbon fluxes in the surrounding landscape. This research is highlighting the heterogeneity of the Arctic carbon cycle and its role in the full Arctic system.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.