Climate induced changes of the subpolar Atlantic and the Baltic Sea: Long-term variability and relevant processes - Cruise MSM12/4a - August 25 - September 09, 2009 - Bremerhaven (Germany) - Stockholm (Sweden)

• Main Author: Pollehne, Falk
• Format: Report
• Language: English
• Published: DFG-Senatskommission für Ozeanographie 2013
• Subjects: Earth Science; Earth sciences and geology; Arctic; Ice; North Atlantic; permafrost; Tundra
• Online Access: https://dx.doi.org/10.2312/cr_msm12_4a; https://www.tib.eu/suchen/id/awi:82a2607e89c2391d4b4d34bb6f71da2bc81d72c7

MSM 12/4a covered those workpackages of the combined proposal with MSM12/4b, Prof. Jürgens, which were related to the distribution of material and processes throughout the whole Baltic gradient (WP 7-9).The primary focus of the cruise concerned the riverine transport of refractory organic matter from the arctic tundra, which increases when these permafrost soils thaw and the distribution within the Baltic Sea. The question if and in which part of the Baltic these large amounts of organic carbon are degraded by bacteria and converted to CO2 was studied in experiments and by means of isotopic markers. In addition to the stocks of organic material in the water those in sediment and sedimenting particles were included in sampling and analysis. Sediment trap arrays, that were sampling particles already for a longer period of time in the major basins of the Baltic, were serviced and changed on this cruise. The study of the inflow of saline North Sea water into the Baltic aimed at a high resolution reconstruction of Holocene variations, their coupling to climate variability in the North Atlantic and their effects on the Baltic ecosystem. Special importance is attached to the time slices of the last 100 years with the opportunity of a coupling to time series measurements, the medieval warm phase and little ice age as historical natural climate variations and palaeodevelopment until 8000 years before today. Respective samples were acquired by means of adapted sampling gear (from multicorer to 20 m gravity corer) in the accumulation basins of the Baltic Sea. On the cruise all planned sampling actions and experiments were performed successfully and in the successive period of data analysis many interesting and new scientific findings could be attained. : MARIA S. MERIAN-Berichte