Argentine Antarctica mainland. Argentina was the only nation to have an Antarctic base for 40 years until the British built a base on the same islands. Argentina bases its claims on this sector of Antarctica on the following grounds: Argentina's claim to the Antarctic Peninsula overlaps with the Antarctic claims of Chile, 53°W to 90°W, and the UK claims, 20°W to 80°W. Currently, there are no attempts by Argentina or any other country to enforce territorial claims in Antarctica. See List of Antarctic territorial claims. None of these claims have international recognition and have been suspended by the Antarctic Treaty in 1961.
Antarctica warming up; particularly strong warming has been noted on the Antarctic Peninsula. A study by Eric Steig published in 2009 noted for the first time that the continent-wide average surface temperature trend of Antarctica is slightly positive at >0.05 °C (0.09 °F) per decade from 1957 to 2006. This study also noted that West Antarctica has warmed by more than 0.1 °C (0.2 °F) per decade in the last 50 years, and this warming is strongest in winter and spring. This is partly offset by autumn cooling in East Antarctica. There is evidence from one study that Antarctica is warming