The study, published in the journal Nature Climate Change on Monday, sheds new light on the most distant part of the world. While scientists knew that Antarctica’s outer regions had been warming for years, they previously thought the South Pole, which was deep in them, was isolated from the increasing global temperatures.
“This emphasizes that global warming is global and moving towards these distant locations,” said Kyle Clem, a post-doctoral research fellow at the University of Wellington, and lead author of the study. Said.
Clem and his team analyzed weather patterns at the South Pole and climate models to examine the warming in Antarctic interior. They found that between the years 1989 and 2018, the South Pole had been warming at about 10 degrees Celsius over the past 30 years and warmed by +0.6 ° C in ten years, three times the global average.
Scientists said the main cause of warming is to increase sea surface temperatures thousands of miles away in the tropics. Over the past 30 years, warming in the western tropical Pacific Ocean – in the north of Australia, close to the equator and Papua New Guinea – meant an increase in warm weather to the South Pole.
“This is the wildest. The most remote place on the planet. Importantly, how extreme temperatures are shaking and changing over the Antarctic interior, and the mechanisms that activate them, the Pacific in 10,000 kilometers (6,200 miles) in the tropical regions of the continent,” Clem said.
Melting sea ice, Antarctic heat waves
Although the South Pole is below freezing point and probably will remain this way, Clem said the warming trend seen at the Pole is linked to what we see on the coast and the Antarctic Peninsula.
“The warming starts from the shore and runs internally,” said Clem.
“As you get closer to the shore where the warming comes, you will start to see more effects. When you reach that point near the freezing point, you will start melting. Or, melting the sea ice and warming the ocean in the Weddell Sea and affecting life in that area,” he said.
Will the climate crisis be blamed?
Initially, scientists found that while the global poles were rising, in the 1970s and 1980s the South Pole actually cooled more than a degree. The team said that the cool period fell on the natural climate patterns that occurred in 20-30 year cycles.
Then the trend quickly reversed, “and suddenly we have almost 2 degrees of warming at the end of the century,” said Clem.
Warming from 1 degree cooling degree to 2 degrees meant a 3 degree increase.
Meanwhile, global temperatures rose about 1 degree Celsius (1.8 degrees Fahrenheit) of pre-industrial levels, and the goal is to keep global median temperatures within 1.5 degrees Celsius (2.7 degrees Fahrenheit) to eliminate the worst effects of the climate crisis.
Clem said that the extreme fluctuation in the South Pole showed that natural variability “masks” the effects of human-induced climate change.
The team found that warming was caused by natural changes in sea surface temperatures for several decades. However, these natural climatic drivers “acted” or reinforced with global greenhouse gas emissions.
“We have natural processes in which global warming and its impact on the climate system will always happen,” said Clem. Said. “It’s quite remarkable when the two work together.”
The science behind warming
In addition to human intervention, greenhouse gas emissions are a few natural processes working behind the scenes to heat the South Pole, the researchers said.
A climate phenomenon called Interdecadal Pacific Oscillation (IPO), which manages ocean temperatures in the Pacific Ocean, turned from a positive phase to a negative phase in the early 21st century. This warmed the western tropical Pacific and caused denser cyclones and storms.
All this has made the South Pole one of the fastest warming places on the planet.
The upper limits of natural variability
Since the temperature records of the South Pole returned only until 1957, scientists could not make a definitive conclusion that warming is driven by human activity.
So they used models that simulate Earth’s climate with greenhouse gas concentrations representing the industrial climate – so without human influence.
In simulations, the team calculated all 30-year trends that could occur in the South Pole in these models. They found that the 1.8 C warming observed was higher than 99.9% of all 30-year trends without human influence.
The authors said the nature of the trend is “remarkable,” although this warming means “the simulated range of natural variability is within the upper limits.”
“Almost anywhere in the world, if it had been warming 1.8C for 30 years, it would have been out of the tables. Said Clem.
However, the result was not 100%. So According to Clem, there is a possibility that the warming in the South Pole occurred only through natural processes. but a small one.