The Expedition ANT-XXV/5
Weekly Reports
16 April 2009: From Punta Arenas into the South Atlantic
24 April 2009: In the South Atlantic to the Vema Channel
30 April 2009: From Vema Channel to the Equator
10 May 2009: Crossing the Equator
19 May 2009: Stop in Las Palmas
25 May 2009: The calm Biscay
Summary and itinerary
On 11 April 2009 Polarstern will start her return voyage from Punta Arenas to Bremerhaven. The cruise will be utilized for continuous investigations of atmospheric and marine properties as well as for energy and material fluxes between ocean and atmosphere. During a short call at Las Palmas on Gran Canaria, parts of the scientific crew will be exchanged on 13 May. The ship will return to Bremerhaven on 24 May 2009.
A number of autonomous measurement platforms for energy and material exchange between ocean and atmosphere will be tested. They are planned for future operations on commercial voluntary observing ships and research vessels. The prime objective of the meteorological working group consists of the remotely sensed composition of aerosol in the atmospheric column. The temporal evolution of aerosol properties will be studied in order to explore aerosol-cloud interactions and to establish meridional gradients of tropospheric aerosols.
The long-term temperature time series from the abyss at the Vema Channel (31°S, 39°W) will be continued. It was initiated in 1972 in international cooperation. Observations with the Acoustic Doppler current profiler (ADCP) in the upper water column supplement earlier observation from lower latitudes of the Atlantic. The expected results will contribute to studies of intra-seasonal and seasonal fluctuation of the main current systems. In addition, these data serve as reference for registrations from moored instruments at the equator at 23°W.
In Las Palms additional participants will embark. They will be trained in the operation of the Parasound system P-70. Trials of the new POSIDONIA installation on the ship are planned en-route to Bremerhaven.
Finally, supervised transports of living animals will be arranged for further molecular genetic and physiological analyses in Bremerhaven.


