This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).
Funding for this award will enable continuation for three years of a program of trace gas measurements in the middle atmosphere (stratosphere and mesosphere) over Thule Air Base, Greenland, using a ground-based millimeter-wave spectrometer (GBMS). The GBMS employs remote sensing to detect and measure molecular rotational emission lines. The species observed are used in monitoring and measuring the chemical and physical state of the polar atmosphere, which undergoes rapid changes during the Winter-Spring period of active observation. The focus is on those species and processes related to stratospheric ozone depletion. Among the advantages of the GBMS technique are that observations are not dependent on sunlight, and that pressure-broadened spectral line shapes can be measured with great accuracy, allowing vertical distribution profiles to be deduced from deconvolution of the observed line shapes. The species to be observed are ozone, carbon monoxide, nitrous oxide, nitric acid, and hydrogen cyanide, and perhaps chlorine monoxide. The observations will continue a series of Arctic observations of the middle atmosphere carried out by the principal investigator and colleagues in the early springs of 2002, 2003, and 2009.
This effort will coordinate with measurements conducted by National Aeronautics and Space Administration/Jet Propulsion Laboratory using the Microwave Limb Sounder on board the Aura satellite. Data collected in the course of these observations will also be archived for accessibility by the general scientific community in the data bank maintained by the Network for the Detection of Atmospheric Composition Change. Articles describing results of the research will be published in refereed scientific journals having world-wide circulation. In addition, the specific research activity will be carried out under an international collaborative effort also involving the Italian National Institute for Geophysics and Volcanology (INGV), and the University of Rome "La Sapienza", with the additional cooperation of the Danish Meteorological Institute (DMI). A University of Rome lidar will operate concurrently with the GBMS, providing key information on atmospheric parameters complementary to the GBMS dataset. INGV personnel will be heavily involved with the operation and maintenance of the GBMS. Both GBMS and lidar will be hosted at Thule Air Base in the laboratories of the DMI, where the instruments are housed in rooms set up and reserved for that purpose. Each participant and their national atmospheric research efforts benefit from the synergies of this cooperative work.
