Cyclones slowing and intensifying - new research

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But when Atlantic storms hit land - like Harvey did in 2017 - the study said the slowdown is a significant 20%.

Global warming is also projected to increase the severity of the strongest tropical cyclones.

Dr Christina Patricola, from the Climate and Ecosystems Sciences Division at University California, Davis, says the findings raise several questions, especially regarding "stalled" tropical cyclones.

There is considerable evidence that global summertime circulation patterns in the atmosphere are slowing as a result of global warming.

Researchers claim that as the planet's poles heat up, pressure gradients around the world are changing, reducing the winds that push on these storms.


"Tropical cyclones are just carried along by the wind, so it makes sense", Kossin says.

Therefore, it would make sense that if the flow around the hurricanes and typhoons is moving slowly, the storms will also be moving slower, which Kossin believes is what he is observing in the data.

This means the more time they spend above land, the more devastation they can wreak with rainfall and storm-induced damages.

According to NOAA, inland flooding accounts for more than 50% of hurricane-related deaths each year.

"What we're seeing nearly certainly reflects both natural and human-caused changes", Kossin said.


Previous research has shown that a warmer climate can hold more water moisture, so when it rains, it rains more.

'This suggests that global warming can enhance rainfall'.

"It is plausible to say that the local rainfall impacts, the impacts from slowing, are equal to and possibly greater than the impacts from increased water vapor in the atmosphere", he said. Instead, it means the tracks of the storms have slowed, allowing them to hover in one location for longer periods of time.

Texas state climatologist John Nielsen-Gammon said "I just need more convincing that there actually has been a 10% motion change". Given that storms in some regions are migrating poleward and already increasing in intensity, cyclones delivering unusually powerful bouts of rain may threaten places not normally in their path.

'These trends are nearly certainly increasing local rainfall totals and freshwater flooding, which is associated with very high mortality risk'. "And, unfortunately, this signal would point to more freshwater flooding". Follow him on Facebook, Twitter and Instagram.


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