Hurricanes also get wetter because of more water vapor in the warmer atmosphere; Scientists have suggested that storms like Hurricane Harvey produced much more rain in 2017 than they would without the human impact on the climate. In addition, rising sea levels contribute to higher storm surges – the most destructive element of tropical cyclones.
A major United Nations climate report released in August warned that nations have delayed curbing their fossil fuel emissions for so long that they will be unable to stop the increase in global warming for the next 30 years, leading to more frequent life-threatening heat waves and severe ones Droughts. Tropical cyclones have likely increased in intensity over the past 40 years, the report says, a shift that cannot be explained by natural variability alone.
Ana became the first named storm of the season on May 23, the seventh year in a row that a named storm developed in the Atlantic prior to the official start of the season on June 1.
In May, scientists from the National Oceanic and Atmospheric Administration predicted there would be 13 to 20 named storms this year, including six to 10 hurricanes and three to five major category 3 or higher hurricanes in the Atlantic. In a mid-season forecast update in early August, they continued to warn that this year’s hurricane season would be above average, pointing to a busy end to the season.
Matthew Rosencrans of the National Oceanic and Atmospheric Administration said an updated forecast suggested there would be 15 to 21 named storms, including seven to 10 hurricanes, by the end of the season on Nov. 30. Ida is the ninth named storm of 2021.
Last year there were 30 named storms, including six major hurricanes, which forced meteorologists to deplete the alphabet for a second time and switch to using Greek letters.
It was the highest number of storms in history, surpassing 28 from 2005, and including the second highest number of hurricanes on record.
Neil Vigdor, Derrick Bryson Taylor, Christine Hauser and Alyssa Lukpat Reporting contributed.