Global Warming Causes Fewer Tropical Cyclones

The atmosphere is becoming more hostile to the formation of tropical storms. There were fewer storms in the early 2010s than there were in the late 19th century, according to a new study.

There are more hurricanes and typhoons than there are people. As the world continues to heat up, those that form are more likely to reach higher intensities.

Tropical storms can cause large-scale death and destruction, so scientists have been trying to understand how climate change will affect them. Climate models suggest the number of storms should decline as global temperatures rise, but they haven't been proven in the historical record. It takes a long time to pick out trends driven by global warming from the data from satellites.

The highest-quality observations are fed into a weather computer model in order to work around the limitations. Savin Chand is an atmospheric scientist at Federation University Australia and is one of the study authors. This gives researchers a realistic view of the atmosphere over time. Chand and his team were able to look for trends over the course of more than 150 years with the help of their new algorithm.

There was a 13 percent decrease in tropical cyclones over the period of 1900 to 2012 compared with the period of 1850 to 1900. Around the time global temperatures started to rise, there was a decline of more than 20 percent. There are different declines in the ocean. The western North Pacific saw 9 percent fewer storms, while the eastern North Pacific saw 18 percent fewer. The results showed a decrease over the past century but an increase in recent decades. Natural climate variations, better detection of storms, and a decrease in aerosol pollution are some of the factors that could explain the short-term increase.

The study provides crucial ground-truth information for evaluating climate model projections of further future changes in cyclone frequencies, according to a tropical meteorology professor at Mississippi State University who was not involved with the paper.

The decrease in tropical storm frequencies is linked to changes in atmospheric conditions that cause warm, moist air to surge upward in the atmosphere, which allows tropical storms to form. Warming is thought to be the cause of those changes. Wood says that the analysis is a lot more than that.

Even if there are fewer tropical cyclones overall, a larger proportion of those that do form are expected to reach higher intensities because of global warming. There is a lot of fuel in the atmosphere.