The PAL study area encompasses a 200 x 500 km region extending from the nearshore coastal zone heavily influenced by seasonal sea ice cover to the open Southern Ocean, and from a northern area where sea ice cover is now limited to only the colder winters, to the south where perennial sea ice cover persists into summer months. In this region, primary production is dominated by unicellular phytoplankton and limited by light availability to the October-April period. The region is characterized by spring phytoplankton blooms that have declined by up to 90% in the northern region since 1978.

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.

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.

 Phytoplankton production in the Santa Barbara Channel supports one of the richest marine ecosystems in the Southern California Bight. The climatology of chlorophyll biomass in the area reveals maxima over the Santa Barbara Basin in the western Channel and along the mainland in the eastern channel where the continental shelf broadens and where two rivers discharge seasonally.

 The primary research focus of the Santa Barbara Coastal (SBC) LTER is on the relative importance of bottom-up processes and allochthonous inputs to giant kelp forests, a highly diverse and productive marine ecosystem that occurs on shallow rocky reefs at the interface of the land-ocean margin. Giant kelp forests are found along the temperate coasts of western North and South America, southern Africa, Australia and most sub Antarctic islands, including Tasmania and New Zealand.

Seven years of oceanic and meteorological monitoring data have been collected in the Georgia Coastal Ecosystems LTER domain from 2002-2009 in order to understand the spatial and temporal patterns of temperature and salinity across the domain. Empirical orthogonal function analysis shows that temperature changes with time are dominated by 1 principal component (explains 93% of the variability) which is strongly correlated with atmospheric fluxes.

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.