Climate change to steer superstorms away from US coast, says study

Climate change is likely to cause stronger and more frequent hurricanes, but may reduce the risk of extreme storms similar to Hurricane Sandy from hitting the US east coast, scientists have claimed.

In a study published in the journal Proceedings of the National Academy of Sciences, researchers used climate simulations assuming a tripling of greenhouse gasses by 2100 to study how future conditions will affect the likelihood of a storm like Sandy hitting the Atlantic coast.

According to NASA, Hurricane Sandy, also nicknamed Superstorm Sandy, was a one in 700 year event. It’s trajectory was extremely unusual, as the storm made a abrupt left turn taking it straight towards New York and New Jersey on the Atlantic coast.

The new study found that such a rare event would become even less likely.  Future atmospheric conditions, the researchers say, would be more likely to push major storms further offshore, away from the vulnerable cities along the Atlantic coast.

Estimates as of June say Sandy may have caused over $68 billion ($43 billion) in damage in the US, making it the second costliest hurricane in America’s history, second only to Hurricane Katrina. At least 286 people were killed by the storm in seven different countries. 

Earlier this year Michael Bloomberg, mayor of New York City, outlined a $19.5 billion (£12.5 billion) plan to protect the city from future natural disasters.

These precautions are still necessary say the scientists, who add that their study only analysed the tracking patterns of hurricanes and did not investigate the frequency at which such events are expected to increase.

While the likelihood of freak storm impacts may decrease, scientists have warned that flooding driven by climate change could devastate coastal cities. In August, a study published in the journal Nature Climate Change named New York, along with Miami, Mumbai and Bangkok, in the top twenty cities most as risk from severe coastal flooding.

The study predicts that average global flood losses could rise from around $6 billion (£3.8 billion) per year in 2005 to over $60 billion (£38 billion) per year by 2050. It attributes this rise to population increases and economic growth in coastal cities, as well as sea level rises caused by climate change. 

These increases assume that at-risk cities invest in flood defences as expected. If cities do upgrade their defences, projections for a worst-case scenario show that their annual losses could be more than $1 trillion (£650 billion).

“If we did nothing about the risk, the flood damages in coastal cities would grow to huge amounts. So that’s really not an option”, study co-author Robert Nicholls, a coastal engineering professor at the University of Southampton, told LiveScience.  

“The bottom line is it shows that flood risk is rising today — it’s happening”, Nicholls said. “All these cities need to be preparing for that.”

Further reading:

‘Climate change has already arrived’, president of the Marshall Islands warns

Coastal flooding could cost vulnerable cities more than $1tn

Flood defence measures lag behind the risks, says committee

Swimming against the tide: the Pacific nations fighting a losing battle with climate change

UN: economic losses from natural disasters total $2.5tn this century