Last week, NASA's DC-8 plane flew over Alaska and Canada, measuring carbon dioxide and methane in the Arctic air. The plane carried five instruments to make these measurements for the Active Sensing of Carbon dioxide Emissions over Nights, Days and Seasons (ASCENDS) experiment. All part of NASA's Arctic Boreal Vulnerability Experiment (ABoVE), the science team is studying how the Arctic is changing in a warming climate.
GCMD keywords can be found on the Internet with the following citation:
Olsen, L.M., G. Major, K. Shein, J. Scialdone, S. Ritz, T. Stevens, M. Morahan, A. Aleman, R. Vogel, S. Leicester, H. Weir, M. Meaux, S. Grebas, C.Solomon, M. Holland, T. Northcutt, R. A. Restrepo, R. Bilodeau, 2013. NASA/Global Change Master Directory (GCMD) Earth Science Keywords. Version 22.214.171.124.0