Climate models gain precision as political scrutiny increases

Climate researchers can now complete attribution studies during ongoing heat waves, linking specific extreme events to human-caused climate change. The studies compare computer simulations of conditions with and without greenhouse-gas emissions to calculate how much more likely an event has become.

Recent applications During a heat wave that hit the eastern U.S. earlier this month, researchers with World Weather Attribution concluded the combination of high temperatures and high humidity would have been virtually impossible without emissions from burning fossil fuels.

A landmark report examining progress and remaining research needs in the field is due July 16 from the U.S. National Academies of Sciences, Engineering and Medicine.

Political and industry response Some Republicans in Congress and members of the fossil-fuel industry have already moved to weaken the credibility of the upcoming report, according to Politico. In May, President Donald Trump stated that some climate models were wrong.

Insurance sector use Insurers use similar computer simulations to estimate how global warming is changing the frequency and severity of weather-related losses and to set premiums. A natural catastrophe specialist at Swiss Re said historical weather records are becoming less reliable guides to future risk. The same specialist noted that models can be useful if their limitations are understood.