Measuring Greenhouse Gases in Meltwater in the Canadian Arctic Archipelago

Project leaders: Anna Michel and David Nicholson, Woods Hole Oceanographic Institution

Research Summary

How significant is methane outgassing during the spring thaw of interconnected lakes, rivers and ocean waters?

In the Arctic Spring, a rapid and significant release of methane, carbon dioxide, and other greenhouse gases occurs over a span of a one to two-week period as frozen waters in interconnected lakes, rivers and the ocean begin to thaw. This period has the highest annual methane release from the coastal ocean.

To study methane release during this thaw, researchers used an innovative technology, called the ChemYak, in shallow, narrow marine waterways near Cambridge Bay, Nunavut. The ChemYak resembles a modern kayak but is equipped with instruments and an engine that self-propels. Its chemical sensors measure dissolved methane, carbon dioxide, oxygen, and other physical variables in the surface meltwaters. The findings revealed unusually high aerial outgassing rates compared to other mechanisms for air-sea methane flux.

By using the ChemYak, researchers advanced the understanding of greenhouse gases released, enabling temporal and spatial chemical mapping. Additional measurements of methane and carbon dioxide outgassing from melting freshwater ponds further supported the evidence of the rapid changes that occur during the spring thaw period.

Read the full research results in Geophysical Research Letters.

This project was funded by the National Science Foundation, USA and Polar Knowledge Canada.