Hurricane Florence will bring 50 percent more rain that it would have if climate change were not occurring, according to a team of researchers using a new computer model. The researchers ran two separate forecasts, one with the temperatures and atmospheric conditions that have actually been observed, and another with the impacts of climate change on moisture, and air and sea surface temperatures removed. They found that the storm was more intense for a longer period, and about 80 kilometers wider in diameter, than it would have been otherwise, according to CBC News.
The planet’s temperatures have increased by about one degree Celsius in the past 100 years, and increased ocean temperatures contribute directly to hurricanes. Unlike past work to attribute specific weather and climate events to climate change, the new research forecasts an event rather than using data observed from one that has already occurred. According to Kevin Reed, one of the paper’s coauthors and a professor at Stony Brook University’s School of Marine and Atmospheric Sciences, this means we have yet to see whether the forecast will be accurate.
“What we’re saying is that in our forecast of Hurricane Florence, that it was 50 per cent higher. This is a forecast multiple days before landfall,” said Reed.
Like Harvey the year before, Florence is projected to slow down now that it’s made landfall, stalling over the Carolinas, giving it the chance to unleash huge quantities of rain. This pattern hasn’t been definitively linked to climate change, but some studies have suggested a connection. However, higher ocean temperatures are a definite result of climate change, and a driver of more intense storms.
The paper has not been peer-reviewed, and many scientists have questioned whether it is really possible to conclusively attribute a single weather event directly to climate change.
According to Penn State Earth System Science Center director Michael Mann:
“I’m a bit skeptical about detection and attribution of specific weather events. I’m unconvinced that the models capture all of the processes relevant to understanding the impact climate change is having on these events.”
However, instead of arguing that climate change may not have influenced Florence at all, Mann suggests the paper could be underestimating its impact. For example, atmospheric blocking patterns, which some scientists believe lead to hurricanes stalling over land, were not factored in to the climate models, according to Mann.
He also points out that climate change is no longer a future possibility, but is now a current reality:
“This is where we see most vividly the death and destruction already being caused by climate change. We must help the public connect the dots here and understand the urgency of acting on climate now.”