While the overall picture of global warming shows a regular rise in overall temperatures, some regions of the Earth are warming faster than others, the Arctic being a prime example. Now a team of scientists has discovered a similar accelerating trend at the opposite end of the world. More than 30 years of meteorological data have revealed that the South Pole has warmed more than three times the global rate since 1989.
The research was carried out by an international team of scientists who examined data from weather stations, observations, and climate models to assess the impact of global warming at the South Pole.
Even though temperatures can vary greatly on the Antarctic continent and we knew that most of West Antarctica and the Antarctic Peninsula experienced a warming trend since the late 20th century, the South Pole was believed to be different. That the interior of Antarctica should not be so sensitive to warming … The truth is that it is.
The South Pole is not immune to warming
The South Pole is within the coldest region on Earth – the Antarctic Plateau . Average temperatures range from -60 ℃ during winter to just -20 ℃ during summer, so temperatures vary greatly over the course of a year.
Most of West Antarctica and the Antarctic Peninsula experienced warming and thinning of the ice sheet in the late 20th century. In contrast, the South Pole, located in the remote, high-altitude continental interior, cooled until the 1980s and has since warmed substantially. These trends are affected by natural and anthropogenic climate change, but the individual contribution of each factor is not entirely clear.
What is the reason for this acceleration in warming?
According to the team’s analysis, the South Pole warmed a total of 1.8 ° C between 1989 and 2018, and has started to accelerate since the early 2000s . For comparison, the combined temperatures of land and oceans across the planet have increased at an average rate of 0.18 ° C per decade since 1981, according to the National Oceanic and Atmospheric Administration (NOAA).
An increase of more than three times the annual average in the last 30 years is not a trivial figure. According to the study, which has been published in the journal Nature Climate Change, this period of warming was mainly due to the natural variability of the tropical climate that has reduced the atmospheric pressure over parts of the Atlantic and, in turn, has brought the air more warm to the plateau where the South Pole is located and probably intensified by the increase in greenhouse gases.
The researchers found that several of the warmest years at the South Pole were associated with unusually warm temperatures in the tropics, and nearly 20% of the temperature variations at the South Pole during the period studied could be related to ocean temperatures in that region.
“ This shows how closely related the Antarctic climate is to tropical variability. Our study also shows how internal atmospheric variability can induce extreme regional climate change throughout the interior of Antarctica, which has masked any signs of anthropogenic warming there during the 21st century, “says Kyle Clem, University of Wellington and leader. from work.
The team is interested in continuing to study how anomalies in the atmosphere around the southernmost continent affect its ice sheet and surrounding seas.
Referencia: Kyle R. Clem, Ryan L. Fogt, John Turner, Benjamin R. Lintner, Gareth J. Marshall, James R. Miller, James A. Renwick. Record warming at the South Pole during the past three decades. Nature Climate Change, 2020; DOI: 10.1038/s41558-020-0815-z
