The new research shows that the South Pole has warmed three times faster than the rest of the planet in the last 30 years due to warmer tropical ocean temperatures.
It has been thought that the south pole is cooler than other parts of the planet as Antarctica’s temperature varies widely according to season and region. But, the recent result shows that things are just different.
Researchers in New Zealand, Britain, and the United States studied the last 60 years of weather station data and created the computer model to show the cause of accelerated warming.
The researchers found that atmospheric temperature over Weddell sea in the southern Atlantic has been lowered due to warmer ocean temperature in the western pacific.
This has increased the flow of warm air over the south pole, therefore warming it by more than 1.83C (about 3.3F) since 1989.
Authors of the research said the natural warming trend was likely boosted by manmade greenhouse gas emissions and could be masking the heating effect of carbon pollution over the South Pole.
“While temperatures were known to be warming across West Antarctica and the Antarctic Peninsula during the 20th century, the South Pole was cooling,” said Kyle Clem, a researcher at Victoria University of Wellington, and lead study author.
“It was suspected that this part of Antarctica… might be immune to/isolated from warming. We found this is not the case anymore,” he added.
The data showed that the South Pole – the most remote spot on Earth – was now warming at a rate of around 0.6C (1.1F) a decade, compared with around 0.2C (0.4F) for the rest of the planet.
The IPO cycle lasts roughly 15-30 years, and alternates between a “positive” state – in which the tropical Pacific is hotter and the northern Pacific is colder than average – and a “negative” state where the temperature anomaly is reversed.
The IPO flipped to a negative cycle at the start of the century, driving greater convection and more pressure extremes at high latitudes, leading to a strong flow of warmer air right over the South Pole.
Clem said that the 1.83C (3.3F) level of warming exceeded 99.99 percent of all modeled 30-year warming trends.
“While the warming was just within the natural variability of climate models, it was highly likely human activity had contributed,” he said.