Warm air doesn’t reach Antarctica as easily as the rest of the globe, but a new study has found that not even the South Pole is safe from the influences of human-driven climate change.
The study, published Monday in Nature Climate Change, found that, in the last three decades, the region has warmed at three times the global rate. From 1989 to 2018, the region saw the largest average warming trend over 30 years, with an increase of 0.61°C per decade. The team of scientists analyzed weather station data from 20 long-term weather stations to measure the warming trends. This finding is major because it had previously appeared that “the South Pole was immune to warming,” author Kyle Clem, a postdoctoral research fellow at Victoria University of Wellington’s School of Geography, Environment, and Earth Sciences, told Earther in an email.
“Our study shows this is no longer the case,” Clem said. “Also, due to the short length of the temperature records and sparse weather station observations across the Antarctic interior, we really don’t know much about this part of the planet. Here, we shed light that the Antarctic interior is susceptible to abrupt and extreme multi-decadal climate swings.”
Along with temperature, the team looked at atmospheric data and wind measurements to assess how much of this warming is beyond human influence and due to natural variability. It turns out that this rise in temperatures can be attributed to lower atmospheric pressure in the Weddell Sea, along the continent’s northern coastline, which is bringing more warm air from the South Atlantic to the South Pole. This is likely due to increased temperatures in the western tropical Pacific, as this event lowered the pressure over the Weddell Sea in the climate models the team used.
While the authors found that this level of warming is within the possible threshold of natural climate variability, they emphasize that greenhouse gas emissions from humans are exacerbating the situation. It’s important to be careful when attributing specific warming events to climate change, Ted Scambos, a senior research scientist at the University of Colorado Boulder’s Earth Science and Observation Center who was not involved in the study, told Earther in an email.
“Despite the inclination to hang this firmly around the neck of global warming, we need to be a bit cautious, as the authors were in their paper,” he said.
Still, study author Clem told Earther he is worried that climate deniers and science opponents may misconstrue these findings to push their agenda. The natural variability of the region makes it incredibly difficult to know humans’ role in what’s happening, but that doesn’t mean that Antarctica is safe from climate change. Even more urgently, at no point do these findings suggest climate change isn’t real.
“None of our results support these types of conclusions,” Clem said. “If anything, our results clearly demonstrate that humans are likely playing a large role and may have caused over half of the recent warming.”
Along with this extreme variability, the lack of temperature data for Antarctica complicates this research. Measurements began only in 1957. That’s why the authors of this study relied heavily on climate model simulations. This helped them gain a better understanding of the role climate change plays in the region’s transformation. Unfortunately, using models adds yet another limitation to the research, because they struggle to accurately simulate Antarctic sea ice. The amount of sea ice cover directly affects the level of warming; the more sea ice there is, the more the Sun’s rays are bounced back into space. However, if there’s less sea ice, more of that energy is absorbed. That doesn’t diminish the value of this research and its findings, though. Science is rarely perfect, after all.
The research still leaves us with many questions, but Clem hopes that these findings will push world leaders and scientists to better prepare for the extreme temperature swings Antarctica will likely face. In recent years, we’ve seen record sea ice loss, green snow, and the breaking of icebergs. These changes can have global effects, especially when ice melts. That can worsen sea level rise. However, so much of Antarctica remains a mystery. More scientists need to research the continent to truly understand how climate change will alter it.