Meridional distributions of deuterium in atmospheric water vapour between tropical and southern polar latitudes

• Main Authors: Gunter Schwarz, Peter Kowski, Susumu Kaneto, Hartwig Gernandt
• Format: Report
• Language: English
• Published: Alfred Wegener Institute for Polar and Marine Research, Research Unit Potsdam/Umweltforschungszentrum Leipzig-Halle/Japan Meteorological Agency/Alfred Wegener Institute for Polar and Marine Research, Research Unit Potsdam 1998
• Subjects: Antarctic; Southern Ocean; The Antarctic; Austral; Antarc*; Ice Sheet; Memoirs of National Institute of Polar Research; Polar Research
• Online Access: https://nipr.repo.nii.ac.jp/?action=repository_uri&item_id=2316; http://id.nii.ac.jp/1291/00002316/; https://nipr.repo.nii.ac.jp/?action=repository_action_common_download&item_id=2316&item_no=1&attribute_id=18&file_no=1

The temporal and spatial variations in the deuterium/hydrogen isotopic ratio of tropospheric water vapour in air masses circulating above the Southern Ocean and the Antarctic continental ice sheet were investigated during the summer season of the 36th Japanese Antarctic Research Expedition (JARE-36) from November 1994 to March 1995. The results of the deuterium analyses of air moisture samples are presented together with water, air and dew point temperatures as functions of latitude. A strong relationship between isotopic composition and latitude as well as corresponding temperatures was found in the region from 20°N to 60°S. Specific circumpolar, meridional and vertical atmospheric circulations and katabatic wind fields dominate in the Antarctic region, hence temperature dependences of the deuterium distribution in Antarctic water vapour are not significant during the short austral summer observation period. The deuterium distributions there are also different from the altitude and latitude effects which are typically for lower latitudes. Furthermore, it is shown that the isotopic composition of air moisture collected at higher latitudes is strongly affected by condensation and precipitation processes during transport, rather than by the evaporation temperature in the source region.