An Israeli study published on Thursday found that climate change is already causing a “considerable intensification” of winter storms in the Southern Hemisphere to a level not anticipated until 2080.
The study published by the Weizmann Institute of Science in the Nature Climate Change journal is part of an effort by scientists around the world to use 30 massive, intricate computer networks to better model and predict climate change.
The study, which compared previous predictions of human-caused intensification of winter storms in the Southern Hemisphere with current storm observations, found that the “bleak” reality was far worse than expected.
“It became clear that storm intensification over recent decades has already reached levels projected to occur in the year 2080,” said a statement from the institute.
The study, led by Dr. Rei Chemke of Weizmann’s Earth and Planetary Sciences Department in collaboration with Dr. Yi Ming of Princeton University and Dr. Janni Yuval of MIT, “shows that current climate models severely underestimate the intensification in mid-latitude storm tracks in recent decades,” the report said.
“A winter storm is a weather phenomenon that lasts only a few days. Individually, each storm doesn’t carry much climatic weight. However, the long-term effect of winter storms becomes evident when assessing cumulative data collected over long periods of time,” Chemke said, explaining that the storms affect the transfer of heat, moisture and momentum within the atmosphere, which consequently affects the various climate zones on Earth.
“One example of this is the role the storms play in regulating the temperature at the Earth’s poles. Winter storms are responsible for the majority of the heat transport away from tropical regions toward the poles,” he said, noting that without their contribution, the average pole temperatures would be about 30°C (54°F) lower.
Chemke also noted the current trends pose “a real and significant threat to societies in the Southern Hemisphere in the next decades.”
The study said it only examined storms in the Southern Hemisphere because the intensification there has so far been stronger than in the north. However, Chemke said that if the trend persists “we will be observing more significant winter storm intensification here in the upcoming years and decades.”
The study also investigated whether these sudden changes could be attributed to natural changes in climate patterns or were caused by external factors such as human activity and found that over the past 20 years, storms have been intensifying faster than can be explained by internal climatic behavior alone, the statement said.
The study also examined why current models were not able to accurately predict the storm changes and found that it was due to changes in atmospheric jet streams.
However, the study found that while there were problems predicting these specific events, most current computer modeling of climate change was accurate.
“The models are doing a very good job at forecasting nearly all the parameters,” Chemke said. “We’ve discovered one parameter for which the sensitivity of the models needs to be adjusted. Changes in temperature, precipitation, sea ice, and summer storm patterns, for example, are all being simulated accurately.”
Still, the research results were alarming, the study said, noting that climate projections for the coming decades are graver than previous assessments, and in this case with dire implications for the Southern Hemisphere.
“This means that rapid and decisive intervention is required in order to halt climate damage in this region,” the statement said.