Ringing Antarctica with data

6 May 2011  •  A total of 673 dropsondes, each packed with weather instrumentation, parachuted to Antarctica and the nearby Southern Ocean between September and December 2010. The dropsondes descended from a fleet of driftsondes, balloon-borne platforms developed through a partnership between NCAR and CNES, the French space agency, as well as scientists in Météo-France.

The driftsondes circled the continent at heights of about 18 kilometers (11 miles) for periods ranging from 43 to 94 days. Over 98% of the driftsonde deployments were successful, reports NCAR’s Charlie Martin. The campaign served as the final chapter of Concordiasi, a project carried out by the Observing System Research and Predictability Experiment (THORPEX) for the International Polar Year. The data gathered by driftsondes and other tools during Concordiasi will help validate observations from newer polar-orbiting satellites, especially radiances from the European satellite MetOp-A, launched in 2006. Shown below are the driftsonde tracks for the period 2–5 November, with each day’s location highlighted.

“This was a phenomenal outcome,” says Steve Cohn, who manages the facility for in-situ sensing at NCAR’s Earth Observing Laboratory. “It is both an engineering success years in the making and an important contribution to Antarctic science.”


Composite of driftsonde launch, 14 October 2010
This composite photo depicting one driftsonde launch from 14 October 2010. A larger version is available. (Photos courtesy Charlie Martin, NCAR.)
Driftsonde tracks from 2–5 November 2010
Shown above are the driftsonde tracks for the period 2–5 November, with each hourly location highlighted. (Depiction courtesy Charlie Martin, NCAR. Google Earth image © Terrametrics; data from Scripps Institution of Oceanography, NOAA, U.S. Navy, National Geospatial Intelligence Agency, and General Bathymetric Chart of the Oceans.)