Plattform Platform	Reise-Nr. Cruise-No.	Zeitraum Period	Projekt Project	Arbeitsgebiet Working area
Sonne1	SO217	25.08.2011 - 16.09.2011		Indian Ocean Makasar Strait Flores Sea

Fahrtleiter Chief Scientist	Institut Institute	Auslaufhafen Port of departure	Einlaufhafen Port of return	Stationskarte Station map	Schiffsroute Trackchart
Kuhnt Wolfgang	Christian-Albrechts Universitat zu Kiel	Makassar	Singapure

Ziel der Reise / Objectives of Cruise:

The Indonesian Throughflow (ITF), with it's main pathway through the Makassar Strait forms a critical part of the global chain of interocean thermohaline links, and influences the size and intensity of the West Pacific Warm Pool (WPWP), which plays a key role in regulating the Earth's heat budget. The consequences of any major changes in ITF volume and physical properties would be dramatic for the tropical ocean-climate system. The transport and thermohaline stratification of the ITF influences the heat and freshwater budgets of both the tropucal western Pacific and eastern Indian Oceans and alters patterns of heat and water vapor exchange with the atmosphere. A reduced ITF would significantly would have strong repercussions on Australasian and African climate. The ITF may therefore be considered a key component for regional climate systems such as the El Nino Southern Oscillation and the Australasian monsoons. The ITF has been observed to vary on seasonal and interannual time scales in response to changing patterns of regional climate. On longer, geological timescales, there is evidence that the ITF was substantially modulated by changes in the geometry of the Indonesian pathways due to sea level changes during the Pleistocene. However, our quantitative knowledge on the magnitude, dynamics, and mechanisms of ITF variability as well as its effect on regional oceanography and climate requires improvement for the ITF to be realistically included in climate (prediction) scenarios. The main objectives of Cruise SO-217 are (1) to determine the isotopic and geochemical characteristics of North Pacific thermocline water and cool South Pacific intermediate water, which form the two main components of the ITF (Gordon et al., 2003); (2) to evaluate the hydrographic profiles of the two main inflow paths, (3) to document changes in the ITF inflow during the late Pleistocene and (4) to test model predictions of a strongly reduced glacial throughflow and significantly changed hydrographic profile in the Makassar strait. To achieve these objectives we carry out a regional multicorer core-top calibration within the Makassar Strait and Java Sea and undertake high resolution measurements of paleoceanographic proxies in piston cores over the last two glacial cycles. The ultimate goal of cruise SO-217 is to reconstruct the variability of the ITF passage through the main bottleneck in the Makassar Strait over the last glacial cycles and to elucidate the role that ITF variability may play during rapid (millennial and centennial) and long-term climate change. R/V Sonne Expedition SO-217 took part from 25.7.2011 to 16.8.2011 between the ports of Makassar (Indonesia) and Singapore. The cruise plan consists of CTD and sediment coring in three main working areas: 1.) North part of the Makassar Strait north of the Labani Channel including Mahakam Delta and one station in the southernmost Celebes Sea: Parasound-transects and stations with CTD, multicorer and long piston-corer in four working areas. 2) Central part of the Makassar Strait south of the Labani-Channel: Parasound-transects and stations with CTD, multicorer and long piston-cores in seven working areas. 3) Southernmost part of Makassar Strait, Flores Sea and eastern part of Java Sea: Parasound-transects stations with CTD, multicorer and long piston-cores in five working areas.

Messungen / Measurements