Tropical cyclones are moving more and more northwards, according to an international study that looked at the rings of trees previously been battered by such storms.
Until now, knowledge of the long-term evolution of the geography and intensity of tropical cyclones (also known as hurricanes or typhoons) has been limited.
However, a study carried out by the Swiss Federal Institute for Forest, Snow and Landscape Research WSL, involving Swiss, Czech, Russian, and South Korean researchers, has now found that such storms are increasingly occurring in regions that they previously avoided.
Analysing the rings on trees – “archives of all the important events in the tree’s lifetime”, according to lead author Jan Altman – the researchers studies a 1,300 km stretch of land running from South Korea to Russia to determine the shifting nature of the storms over the past 200 years.
“Our results show that affected regions were once only marginally under the influence of typhoons,” said Altman in a WSL press releaseexternal link; in other words, the storms are moving northwards.
Whether this shift is caused by climate change or by natural variability over the long term was not clear. However, what is clear is that the areas affected are less capable of adapting and dealing with the damages, having been unused to such storms in the past.
The results have been published in the journal Proceedings of the National Academy of Sciences (PNAS).