showing 6 of 6 learning pages IN: Life
Antarctica is best known for its charismatic penguins, seals and whales. However, these are only the most visible members of a thriving Antarctic ecosystem, much of which remains largely unseen. Under the water and beneath the ice, a vibrant community of animals found only in Antarctica thrives in cold, oxygen-rich waters. From glass sponges and colossal squid to notothenioidei (a group of fish with antifreeze proteins in their blood) and enormous sea spiders the size of dinner plates, Antarctica and the Southern Ocean support an incredible diversity of unique life, each species uniquely adapted to the conditions of the South.
Antarctica is a continent of great extremes. Inside the Antarctic Circle summer brings 24 hours of sunlight, and winter brings 24 hours of darkness. The average temperature at the South Pole is -18°F (-30°C) in the summer, and -76°F (-60°C) in the winter. On the coast, winds have measured more than 170 knots (195 mph / 310 kph). Antarctic species have adapted to Antarctica’s seasonal extremes and cold, windy conditions with many unique adaptations.
Sea ice is a crucial component of our planet’s climate system, and one that is highly vulnerable to climate change and variability. Antarctic sea ice is also a critical habitat for marine life, including penguins and seals. Antarctic sea ice is changing, with impacts on Antarctic penguins and important global ocean currents.
Almost all Antarctic life begins and ends in the Southern Ocean. As the global climate changes, the Southern Ocean is becoming warmer and more acidic, which is having impacts on many Antarctic species. On the West Antarctic Peninsula, this is happening faster than almost any other place on earth. Scientists report that Antarctic krill swarms and some penguin species appear to be migrating southward to cooler waters. Some colonies of ‘true’ Antarctic species, such as Adélie penguins, have disappeared, while species adapted to warmer conditions flourish.
Sea ice is more than just frozen ocean. Below the surface it is a vibrant ocean oasis, and a vital habitat for life in Antarctica. Billions of microscopic sea plants live underneath the ice, providing food for Antarctic krill and other small crustaceans, which form the foundation of the Antarctic food chain. The sea ice surface is also a critical breeding ground for emperor penguins. In some parts of Antarctica, winter sea ice cover is declining dramatically. Reduced sea ice cover has a domino effect, impacting Antarctic ecosystems from tiny plants to penguins, seals and whales.
Antarctica is a polar desert: around 99% of the continent is permanently covered in ice. Small ice-free areas are home to extremely rare, uniquely-adapted species found nowhere else on the planet. For those hardy species that have managed to gain a foothold on the ice-free land, life is a constant balancing act as they seek out enough food, shelter and water to survive. The climate crisis is threatening the delicate balance that allows these terrestrial ecosystems to survive.