Scientists from the University of Chicago were able to explain for the first time the phenomenon of more severe storms in the southern hemisphere of the Earth. The results of the work were published in the journal Proceedings of the National Academy of Sciences (PNAS).

Ever since the conquest of South America, sailors have known that storms in those parts are much more severe than in the Northern Hemisphere. This has been proven using satellite data. The Southern Hemisphere does indeed have more storms, stronger jet streams and more intense weather events that are about 24 percent more active than the Northern Hemisphere. However, the cause could not be found.

In order to identify the mechanism, experts have collected extensive satellite information, observations, and existing theories and combined them into a physical climate model. They then gradually removed various variables and quantified the effect of each on the storms.

Related materials: Last breathScientists have named the date of death of all life on Earth. How exactly will this happen?March 27, 2021It will be hotHell heat, mass extinctions and forests on fire: what to expect from global warmingFebruary 9, 2020

The first variable was topography: large mountain ranges disrupt the airflow, which reduces storms, and there are just more mountain ranges in the Northern Hemisphere. When the scientists leveled every mountain in the model, about half the difference in storm strength between the two hemispheres disappeared.

The other half was related to the circulation of the ocean: water moves around the globe like a very slow but powerful conveyor belt. Descending in the Arctic, it passes along the ocean floor, rises near Antarctica, and then flows near the surface. This creates a difference between the two hemispheres. When the scientists eliminated this flow from the model, they noticed that the second half of the differences in storm intensity disappeared.

In addition, after analyzing the last decades of observations, the researchers noticed that the storm asymmetry has increased compared to the 1980s. That is, the Southern Hemisphere becomes even more active, while the changes in the Northern Hemisphere were insignificant. They attribute this to oceanic changes in the Southern Hemisphere. They also occur in the North, but this effect is offset by the absorption of sunlight due to the melting of sea ice and snow.