The structure of zooplankton communities has a significant impact on vertical flux of organic material and cycling of elements in the sea, thus climate-induced changes in zooplankton abundance and species composition have the potential to dramatically affect biogeochemical cycles. The West Antarctic Peninsula (WAP) is one of the most rapidly warming regions on Earth, with documented changes in temporal and spatial distribution of the zooplankton community, and in annual peak organic particle export as measured by sediment traps.

A conspicuous feature of the Western Antarctic Peninsula (WAP) continental shelf is the presence of deep submarine canyons that extend from the shelf break to the land margin, where during summer large colonies of breeding Adélie penguins occur.

Sea ice changes in the greater PAL LTER study region are occurring 29% faster than the fastest sea ice changes in the Arctic. Over 1979-2006, the sea ice season has become 83 days shorter in the greater PAL LTER area versus 59 days shorter in the greater Chukchi Sea area in the Arctic (though the latter includes twice the area effected). We review the physical processes and potential feedbacks contributing to these polar sea ice changes to better reveal high latitude climate sensitivity and its implications for polar marine ecosystems.

Climate warming is predicted to have pronounced effects on biodiversity, particularly the biogeography of organisms, such that species’ range distributions should contract at warmer and expand at cooler range margins, via influences on population-demographic processes, resulting in overall higher latitudinal or elevational displacement of individuals.

Palmer LTER has as its focus the marine continental shelf and marginal sea ice zone ecosystems off the west coast of the Antarctic Peninsula. It is a marine pelagic and coastal site strongly influenced by the formation, extent, duration and retreat of sea ice. Over the past several decades sea ice duration has declined by 90 days and no longer persists into the summer period in our study region. At the same time, the mean wintertime (DJF) surface air temperature has increased by 6°C.