Thursday, September 7, 2017

Guardian -- Twin megastorms have scientists fearing this may be the new normal

Destructive force of Irma and Harvey has Trump expressing awe, but those in power should focus on the environmental causes

Are mega-hurricanes Harvey and now Irma, and warmer sea surface temperatures in the Caribbean and Gulf of Mexico this year a coincidence? Or is global warming fueling these massive storms?

Experts have been warning that such disastrous storms will become more frequent in a warming world. Are Harvey and Irma a sign of what's to come?

One week after the record deluge in Texas as the result of Hurricane Harvey, Irma, the biggest hurricane ever measured in the mid-Atlantic, is tearing through the Caribbean.

Hurricane Irma, a category-five storm, is destroying homes and threatening lives in the Leeward Islands with 185mph winds and 11ft coastal surges, and in the coming days it is forecast to hit Puerto Rico, Haiti, Dominican Republic, Cuba and Florida. The governor of Florida has already declared a state of emergency.

For Donald Trump, these twin megastorms are a source of awe. Hurricane looks like largest ever recorded in the Atlantic! he tweeted of Irma on Wednesday. Even experts have said they’ve never seen one like this! he posted of Harvey last week.

[Does it even cross President Trump’s mind that these two events might be a result of climate warming because of human expansion of the "greenhouse effect" or is he blind to that probability]

But for many scientists, they are a worrying sign of a new normal in which extreme weather events become more intense as a result of manmade climate change. Rather than expressing astonishment, they say policymakers need to strengthen long-term countermeasures and act more effectively on reducing carbon emissions.

Even I as a climate scientist am startled to see another potentially devastating storm in this region so shortly after Harvey, said Anders Levermann, of the Potsdam Institute for Climate Impact Research. Unfortunately, the physics are very clear: hurricanes get their destructive energy from ocean heat, and currently water surface temperatures in this region are very high.

Climatologists are careful to point out that rising greenhouse gas emissions are not the sole cause of hurricanes, which buffet the Caribbean and the Gulf of Mexico around this time every year. But there is strong evidence that warming temperatures and rising sea levels are increasing the destructive power of storms.
  

 By Jonathan Watts