New research published in the Journal of the American Meteorological Society points to changes in ocean-sea ice interactions, moderate temperature fluctuations, and diverse responses to sunlight.

A new study recently published in the Journal of the American Meteorological Society shows changes at Earth’s poles, including changing ocean and sea ice dynamics, weaker temperature extremes, and different responses to solar radiation at the north and south poles, suggesting a long-term change. suggests. The cyclical warming trend may play a bigger role in the Southern Ocean’s record low ice extent in 2023 than previously thought.

three articles Climate Magazine (JCli) It shows that the Arctic and Antarctic are adapting to a warming climate through fundamental changes in regional climate dynamics.

The Antarctic ocean-sea ice system can change dramatically.

A paper by Will Hobbs and colleagues from the Australian Antarctic Partnership Program at the University of Tasmania highlights evidence that the Antarctic sea ice area may be exhibiting a “regime shift”. Although ice in the Southern Ocean plays a critical role in Antarctica’s climate, for example by reflecting heat from the sun, the extent of summer sea ice has become increasingly variable since 2006 and is more closely related to the previous month’s sea ice. usually more than atmospheric factors causing it. The authors’ statistical analysis suggests that the interaction between sea ice and the underlying ocean may be fundamentally changing (perhaps associated with global warming), resulting in increased variability.

“Perhaps the most striking change for scientists is that the recent extreme fluctuations over the past decade cannot be explained by the atmosphere alone,” Hobbs said in an AAPP news release. “The AAPP study shows that the changes we see—how much the average state of sea ice can change and how long those changes can persist—are controlled by ocean processes. This is further evidence that changes in the ocean are likely the secret behind what’s happened in recent decades.”

Antarctica absorbs more energy than the Arctic.

Meanwhile, satellite data show differences in how the Arctic and Antarctica respond to rising temperatures, according to a new paper by Hamish D. Prince and Tristan S. L’Equiere of the University of Wisconsin-Madison. Both poles receive more solar energy as melting sea ice reduces the reflectivity of the regions. This can affect the temperature gradient between the poles and temperate zones that defines much of the climate system. This study shows that the warming Arctic radiates a nearly comparable amount of this increased heat back into space, and that the region’s net energy imbalance remains virtually unchanged despite rapid ice melt. However, Antarctica does NOT radiate more heat energy into space; This means that solar radiation is absorbed by the climate system there, which can affect both the Southern Ocean and the Earth’s atmosphere and latitudinal heat balance.

“Our study provides a robust, observable record of a fundamental aspect of the climate system. Unlike the Arctic, where increased solar absorption is offset by thermal radiation, the surface temperature of the Southern Ocean remains insensitive to increased absorption, storing additional energy,” says Prince. “The global impact of this polar opposite response on albedo reduction may be far-reaching but is generally unknown.”

Melting sea ice reduces seasonal extremes of temperature, especially extreme cold, in the Arctic.

The third paper was written by Igor Polyakov and colleagues from the University of Alaska Fairbanks. It found that the gap between summer extreme highs and winter lows in the Arctic has narrowed since 1979 as melting sea ice opens up moist ocean air. The authors found that the average surface air temperature in the Arctic has increased by about 0.62°C over the past decade. While the average has increased, summer extremes have become 25% colder and winter extremes 200% warmer since 1979; This means that the decline in extreme temperatures is only expected to continue as the Arctic warms.

“Our study shows a fundamental shift in the Arctic climate system towards increased mobility and a closer connection between the atmosphere, ice sheet and ocean,” says Polyakov. “This strong coupling makes understanding the behavior of the system very difficult and requires a multidisciplinary approach in the study of Arctic climate change.”

2023 Minimum Sea Ice – El Niño? Or not?

Finally, an article by Till Kuhlbrodt and colleagues from the United Kingdom American Meteorological Society Bulletins (BAMS) It predicts that record high sea surface temperature in the North Atlantic and record low sea ice extremes in Antarctica in 2023 are similar to what we might expect to see in a world reaching the 3°C global warming threshold. Although many factors, including El Niño, have been suggested as major drivers of last year’s extremes, the authors believe these explanations may not be sufficient. They note that increasing trends in radiative forcing have been strong in recent years, with extreme sea surface and sea ice temperatures evident 8 to 9 months before the strongest effects of El Niño.

Till Kulbrodt (University of Reading) says: “Last year’s extreme events in the North Atlantic and Southern Ocean are worrying because they are a far cry from the events we saw 40 years ago. While accelerating global warming is an important factor, our analysis of ocean data shows that ocean regime change is “It shows that it can also play a critical role.”