COBRA (impact of COmbined iodine and Bromine Release on the Arctic atmosphere) is a UK IPY (International Polar Year) consortium that aims to investigate the release mechanisms of iodine in the Arctic and the potential combined effects of iodine and bromine on its atmosphere. The team measured reactive inorganic halogens (BrO, IO, OIO, I2), O3, Hg, HOx, HCHO, NOx, VOCs and reactive halocarbons from temporary laboratories located on the eastern shore of Hudson Bay, north of Kuujjuarapik, during February-March 2008. Met balloons and O3 sondes were launched daily. COBRA set up an ice camp and flux chamber experiments ~500 m into the bay to directly measure halogen emissions and ozone deposition, and measured physical, chemical and biological characteristics of the sea-ice (and potentially of frost flowers) at different depths. The project is linked with OOTI, which carried out a simultaneous field experiment at Kuujjuarapik.

This is the high frequency (10 Hz) eddy covariance (EC) measurements which mainly contain the wind data, ship motion data, gas concentration data and the underway measurements. These data were measured on summer 2019 during two Arctic cruises JR18006 (from and to Aberdeen, UK and visited the Barents Sea ) and JR18007 (from Harwich, UK to Svalbard and visited the Greenland Sea). These EC data can be used to directly calculate the air-sea CO2 and sensible heat fluxes. The EC system was deployed on RRS James Clark Ross by Thomas Bell and Mingxi Yang (Plymouth Marine Laboratory). Please see Dong et al., (2021) for details of these EC data. Eddy covariance air-sea CO2 flux measurements were made possible by funding from the NERC ORCHESTRA (NE/N018095/1) and European Space Agency AMT4oceanSatFluxCCN (4000125730/18/NL/FF /gp) projects.