CA 11-12 XXVII ita. Esp. New Zealand

Extract from the Italian XXVII antarctic expedition report

The launches of XBT probes were carried on along the track Christchurch (NZ)-Antarctica. XBT casts began on 13/01/2012 18:45 at 46°S/173.55°E and ended on 19/01/2012 at 66°S/176.54°E, the sampling rate was 15 miles nautical.
During the southward journey 99 probes have been used of which 82 showed no operating problems, while 17 launches failed due almost entirely to the contact of the cable conductor with the hull of the ship.
Figure1 shows XBT map and the thermal section of the sub-surface layer. Italian investigations on the thermal structure across the ACC, started in 1994 in the framework of the CLIMA project and nowadays have a relevant climatological significance both for the long period covering and the repetition of measurements along the same track.

Figure1: Map of XBT launches in the period 13-19/03/2012 (left) and section of temperature relative to the layer 0-760m, from New Zealand to Antarctica (right)

A similar activity, for a total of 17 probes, was carried out during the return of the vessel between the latitudinal band of 65°S/178.86°E and 60.5°S/179.357 in correspondence of the main frontal systems in the area of the Antarctic convergence.

Figure 2: Map of XBT launches in the period 14-15/02/2012 (left) and section of temperature relative to the layer 0-760m, from Antarctica to New Zealand (right).

http://www.pnra.it/biblioteca/docs/rapporti_campagna/RapFin2012.pdf