![]() ![]() In addition to rising sea levels, meltwater would slow down the world’s ocean circulation, while changing wind belts may affect the climate in the southern hemisphere. Given their size, even small losses in the ice sheets could have global consequences. If all the ice sheets were to melt due to global warming, Antarctica would raise global sea levels by at least 183ft (56m). The three ice sheets that cover the continent contain around 70 per cent of our planet’s fresh water - and these are all to warming air and oceans. Scientists say protecting at least 30 per cent of the oceans with a network of sanctuaries is key to allow marine ecosystems to build resilience to better withstand rapid climatic changes. Rapid warming has already caused a significant southward shift and contraction in the distribution of Antarctic krill - a keystone species, campaigners said.Ī recent Greenpeace expedition to the Antarctic also confirmed that Gentoo penguins are breeding further south as a consequence of the climate crisis. The Antarctic ice sheet is losing mass three times faster now than in the 1990s and contributing to global sea level rise. While scientists are looking into the complex dynamics between global heating and sea ice trends, climate breakdown is evident in the region, with some parts of the Antarctic warming faster than anywhere else on the planet. Pictured: Penguins walking on sea ice in Antarctica (stock image) Since the late 1970s, Antarctic sea ice was increasing by about one per cent per decade, and we saw record winter maximums in 20. Since the late 1970s, Antarctic sea ice was increasing by about one per cent per decade, and we saw record winter maximums in 20.īut by the following year this value fell to its lowest in 40 years, and it has stayed lower-than-average ever since. While computer models predicted Antarctica's sea ice would face a similar decrease to that in the Arctic, up until recently, the opposite was happening. ![]() However, the Arctic is constrained by land masses, so the sea ice forms and extends throughout Europe, North America, Greenland and Asia. The Antarctic is surrounded by a vast ocean through which sea ice can extend, but this also makes it susceptible to melting by the summer heat. The rate of sea ice loss between the two continents differs in part due to their location and proximity to other continents. The extent of sea ice is defined as the area in which the concentration of ice is at least 15 per cent.Īntarctica's sea ice extent is highly variable, but in the Arctic it has been disappearing by up to 13 per cent a year, thought to be a result of climate change. The Antarctic is surrounded by a vast ocean through which sea ice can extend, but this also makes it susceptible to melting by the summer heat (stock image) 'Nevertheless, the sharp decline in sea ice extent since 2016 has fueled research on potential causes and whether sea ice loss in the Southern Hemisphere is developing a significant downward trend,' they wrote. This could be a result of the winds causing strong waves to break up the weaker areas of ice, or pushing it into warmer waters further out to sea.ĭespite the last two years reporting record lows in annual minimum sea ice, the experts say it is not yet indicative of a downward trend.įour of the five highest minimums have occurred since 2008, and the value appears to be decreasing by only about 0.9 percent per decade. This has created a pressure gradient that has driven these warm westerly winds towards the continent.Īccording to the NSIDC, sea ice on a long stretch of the Pacific-facing coastline of Antarctica is 'patchy and nearly absent'. On top of this, there is a strong 'Amundsen Sea Low' (ASL) – a centre of low atmospheric pressure over the south of the Pacific ocean and off the coast of West Antarctica. Indeed, a study from 2003 found that the SAM has become 35 per cent more positive since the 1980s, which the authors link to climate change. This warmth is thought to be the result of unusually high air temperatures to the west and east of the Antarctic Peninsula in 2022 which, according to the BBC, have been about 2.7☏ (1.5☌) hotter than the long-term average. However, this season the winds have brought warm air which has contributed to more melting. This results in stronger winds over the ice which can help to keep it cool. ![]() This movement, and the resulting change in atmospheric pressure, is the SAM, with a positive SAM meaning the belt of wind is contracting towards Antarctica. ![]()
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