Atmospheric moisture transport across the Southern Ocean via satellite observations

• Published in: Journal of Geophysical Research 1999-04, Vol.104 (D8), p.9229-9249
• Main Authors: Slonaker, Richard L., Van Woert, Michael L.
• Format: Article
• Language: English
• Subjects: Earth, ocean, space; Exact sciences and technology; External geophysics; Marine; Meteorology; Water in the atmosphere (humidity, clouds, evaporation, precipitation)
• ISSN: 0148-0227; 2156-2202
• DOI: 10.1029/1999JD900045

Meridional moisture transport across the Southern Ocean was measured using a combination of TIROS operational vertical sounder and special sensor microwave/imager satellite data from 1988. Satellite and radiosonde estimates of moisture flux compare favorably near Macquarie Island (54.5°S, 158.9°). The zonally averaged, vertically integrated, moisture flux values across 50°S and 60°S are −31.8 and −15.2 kg m−1 s−1, respectively. Resulting moisture convergence for the 50°–60°S latitude band is 636±50 kg m−2 yr−1, about 50% larger than indicated by contemporary studies using radiosondes or atmospheric analyses. Within this latitude band the poleward moisture transport peaks in the South Pacific sector near 135°E, with a secondary maximum in the Amundsen Sea sector close to 135°W. There is a dramatic moisture flux discontinuity across the Antarctic peninsula and the tip of South America near 45°W, with equatorward moisture transport at all latitudes in the Weddell Sea sector. A regional study of West Antarctica indicates large poleward moisture flux is accomplished through the Bellingshausen and Amundsen Seas only.