Last updated June 21, 2018 at 1:37 pm
US study reveals significant slowdown over 70 years.

iStock. Credit: Ramon Berk
Tropical cyclones are slowing down and spending longer over the land they cross, with the potential to wreak even more havoc.
Research by the US National Oceanic and Atmospheric Administration suggests their translation speed (the rate they travel across the planet) has slowed by an average of 10 per cent globally over the past 70 years.
In Australia, it is 19 per cent, but we’re far from the worst off. It is 30 per cent and 20 per cent respectively over land areas affected by western North Pacific and North Atlantic tropical cyclones.
The researchers say global warming is projected to increase the severity of the strongest tropical cyclones, but warming may bring potentially more serious effects, such as the general weakening of summertime tropical atmospheric circulation.
In addition to circulation changes, anthropogenic warming causes increases in atmospheric water-vapour capacity, which is expected to increase precipitation rates. Rain rates near the centre of tropical cyclones are also expected to increase, along with increasing global temperatures.
The paper published in Nature.