Global warming will have a varying effect on weather systems depending on which hemisphere they are in, according to new research from MIT’s Paul O’Gorman, who found that the warming of the planet will affect the availability of energy to fuel large-scale weather systems that occur at Earth’s middle latitudes.
O’Gorman found that more intense storms will occur in the Southern Hemisphere throughout the year, while the Northern Hemisphere will only see intense storms in the winter.
The differences are due to the fact that, though the atmosphere will get warmer and more humid due to global warming –- both wonderful fuels for extratropical storms and large-scale weather systems -– not all of the warming will occur in the same location within the atmosphere.
For example, if the warming is greater in the lower part of the atmosphere, this will provide fuel for storms and intensify the storms at sea level. However if the greater part of the warming is higher up in the atmosphere, this will lead to weaker storms.
As a result of the fact that during the Northern Hemisphere’s summer the warming is greatest at higher altitudes, that hemisphere will see weaker storms.
Sadly, according to O’Gorman, this will have a looping effect on the climate. Fewer extratropical storms during the summer in the Northern Hemisphere could lead to increased air pollution, as “there would be less movement of air to prevent the buildup of pollutants in the atmosphere,” says O’Gorman, the Victor P. Starr Career Development Assistant Professor of Atmospheric Science in MIT’s Department of Earth, Atmospheric and Planetary Sciences.
Conversely, stronger storms year-round in the Southern Hemisphere will lead to stronger winds over the Southern Ocean which will impact worldwide ocean circulation, thus affecting the entire planets climate.