Chapter 5 Gas Fluxes and Dynamics in Polynyas

Abstract

Abstract High biological productivity and active ice formation make polynyas prime air–sea exchange sites for a number of radiatively- and biologically-active gases, such as carbon dioxide and dimethylsulfide (DMS). Limited observations, to date, have shown that polynyas are generally sources to the atmosphere for biogenic gases (e.g., DMS, oxygen, methylhalides) but sinks of CO2, which is drawn down both by primary production coupled with organic carbon export and by high solubility in the cold, high-salinity waters typical of polynyas. However, this simple summary belies large data gaps, and our conceptual models of gas dynamics in polynyas are riddled with untested assumptions. The most important needs for additional research and information are in wintertime and transition-period processes, ice biogeochemistry and permeability, and climate change feedback processes.