RISING SEA LEVELS IN ANTARCTICA By Lily Global sea levels are currently rising at an average rate of 1.8 mm per year since 1961, and 3.1 mm per year since 1993. The main contributions for this rise are from melting glaciers and ice caps, and thermal expansion of the ocean. In addition, the extent of polar snow and ice cover has been receding. Understanding the Holocene Sea level rise, helps to contextualise the rate of sea level change. The IPCC, which stands for The Intergovernmental Panel on Climate Change, is an intergovernmental body of the United Nations responsible for advancing knowledge on human-induced climate change. They have currently estimated the global sea level rise to be around 1.8 ± 0.5 mm per annum. The melting of mountain glaciers and ice caps accounts for quite a lot of this rise, and this may be because smaller glaciers, which also tend to be steeper, are more sensitive to global warming. Over the last 15 years, glaciers around the Antarctic Peninsula have contributed 0.19 ± 0.045 mm per year to sea level rise. In 2021, the Earth’s northern ice cap showed the impacts of the climate crisis. The Arctic sea ice reached its annual minimum, at the second lowest extent seen in four decades. On 15th September 2021, the ice was measured at 3.74m sq km, which marked only the second time that the extent has fallen below 4m sq km in the current record.
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THE CHRONICLE
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