Ecosystems in Antarctica and the surrounding Southern Ocean are shaped by extreme conditions and finely balanced interactions among ice, ocean, atmosphere, and living organisms. These systems are particularly sensitive to environmental change, making them important indicators of how climate change affects biological processes. For this reason, polar ecosystems occupy a central place in the Count of Krigsvold’s educational work.
Antarctic ecosystems are relatively simple compared to those in lower latitudes, but they are highly specialized. Marine food webs are often organized around a small number of key species, such as phytoplankton and krill, which support higher trophic levels including fish, seabirds, seals, and whales.
On land, life is limited primarily to microorganisms, lichens, mosses, and invertebrates that are adapted to cold, dry conditions and short growing seasons. These terrestrial communities are sparse but resilient, relying on narrow ecological niches.
Because polar ecosystems operate within narrow environmental thresholds, even modest changes in temperature, ice cover, or nutrient availability can have disproportionate effects. Reductions in sea ice alter habitat availability and affect the timing and extent of primary production in the ocean.
Changes in ocean temperature and circulation can influence the distribution and abundance of krill and other foundational species, with cascading effects throughout the food web. On land, warming can increase biological activity but also introduce new stresses, including changes in moisture availability and the potential for non-native species introduction.
Some polar organisms exhibit adaptive capacity, including shifts in distribution, changes in life cycle timing, and physiological tolerance to new conditions. However, the pace of environmental change may exceed the ability of many species to adapt, particularly those with long life cycles or limited dispersal.
Ecosystem responses are therefore heterogeneous. Some communities may reorganize or expand, while others experience declines or loss of function. Understanding these dynamics requires long-term observation and integration of biological, physical, and chemical data.
Antarctic and Southern Ocean ecosystems are linked to global biological systems through migration, nutrient cycling, and climate feedbacks. Many species that depend on polar regions spend portions of their life cycles elsewhere, connecting polar changes to ecosystems far beyond Antarctica.
Disruptions in polar ecosystems can thus have implications for marine biodiversity, fisheries, and ecological stability at regional and global scales.
Endangered ecosystems in polar regions illustrate how biological systems respond to environmental change under extreme conditions. By studying these responses in Antarctica and the Southern Ocean, researchers gain insight into the limits of ecological resilience and the mechanisms that sustain life in a changing climate. This understanding contributes to a broader appreciation of how climate change reshapes ecosystems worldwide.