According to a recent study, climate change caused by man was the driving force behind the devastating and deadly rainfall of Hurricane Maria.
Maria hit Puerto Rico on September 20, 2017 as a super hurricane with winds of 155 miles per hour. The record storm caused damage of more than $ 90 billion, with independent mortality estimates ranging from 2,975 deaths to "more than 5,000."
The authors of the new study Geophysical Research Letters concluded that a hurricane at Maria's level "is almost five times more likely to be formed now than during the 1950s, an increase due in large part to the effects of human-induced warming" .
How does global warming lead to extreme deluges? As the lead author, David Keellings, explained, it is the combination of long-term key changes in climate "like the atmosphere is getting warmer, sea surface temperatures are rising and there is more moisture available in the atmosphere."
These findings, along with similar studies on how Hurricane Harvey worsened climate change, underscore The warning issued by many scientists about the impact of Maria and other super hurricanes: global warming is fueling these increasingly intense and destructive storms.
"This study reaffirms what many of us have come to the conclusion, namely, that climate change has worsened the impacts of devastating recent hurricanes like Maria," climatologist Michael Mann told Think Progress in an email. "As this study shows, the warmer oceans were responsible for the extreme rains and floods that Puerto Rico experienced. I would like to add that warm temperatures close to the record also played a role in the rapid intensification of the storm in a category five monster. "
For this latest study, the researchers analyzed precipitation data from 35 historical weather stations for the 129 hurricanes that hit the island since 1956, which was the first year with reliable records.
They concluded that Maria generated the maximum daily maximum rainfall for the island among those 129 storms, an impressive 1,029 millimeters (41 inches). The next closest hurricane in the historic record was 774.9 mm (30.5 inches), a total of 10 inches less.
Then, the authors used a statistical analysis "that explains the natural climatic variability and long-term climate change influences on extreme rainfall" to determine the influence of climate change caused by man in the rain.
They found an increase of almost five times the chances of such an extreme flood in 2017 compared to 1956, mainly due to climate change.
Clearly, the United States needs to be prepared for more Harveys and Marias, due to the warming that has already occurred. But these super storms and their floods will continue to become increasingly intense in the coming decades until we reduce emissions with enough intensity to reduce and then stop human-caused global warming.