Research Unit 1b (Topic 1)

Global change effects on polar ecosystems and biogeochemistry

Rapidly declining sea ice and collapsing ice-shelves, changes in wind forcing, warming and acidification strongly affect the polar oceans. These climate-driven changes have unknown consequences for polar ecosystems, biodiversity and biogeochemical fluxes, on which baseline knowledge is still lacking.

Our research therefore focuses on the causes of Arctic sea ice decline and its impact on ecology and biodiversity, as well as the physical, chemical and ecological changes occurring in the Southern Ocean and their feedbacks on the global climate system. We are concerned with the risks of commercial use of the polar oceans and aim at assuring sustainability. To address these questions, we rely on field work, laboratory studies, numerical modelling and the integration of historical data. Long-term observations at selected sites and transects play a particularly important role.

Over recent years, we improved understanding of variability in sea-ice volume, primary production and vertical fluxes of biogenic material. Long-term observations revealed profound and rapid ecosystem changes in response to a warm-water intrusion into Fram Strait. We also documented poleward advection of warming water and changes in the uptake of anthropogenic CO2 in the Southern Ocean. For the Antarctic Weddell Sea, our scientific foundation led to proposing a Marine Protected Area.

Workpackages

WP 4: Arctic sea ice and its interaction with ocean and ecosystems

Mission statement: To provide evidence and understanding of the causes and consequences of variation in sea ice cover for the hydro-, bio- and geosphere of the Arctic Ocean and beyond.

Principal Investigators: Christian Haas, Benjamin Rabe

WP 5: Southern Ocean physics, biodiversity, and biogeochemical fluxes in a changing climate

Mission statement: To assess the changes that occur in the Southern Ocean, identify the processes that link physics, chemistry and biology, and determine the feedback mechanisms to the global climate system.

Principal Investigators: Volker Strass, Bettina Meyer

WP 6: Large scale variability and change in polar benthic biota and ecosystem functions

This Workpackage targets the functional role of the benthic compartments of both polar biospheres (i.e. the sediment-water transition zone, benthic organisms, their demersal and endotherm predators and pelagic prey) in providing ecosystem functions and services, particularly biodiversity, nutrient recycling, and flow of energy and matter. The geographical focus is on regions for which we already built a considerable knowledge base, i.e. the Antarctic Weddell Sea and Peninsula region and the Arctic Fram Strait including the AWI-HAUSGARTEN – Kongsfjord area. 

Principal Investigators: Thomas Brey, Hans-Otto Pörtner