The links between hurricanes and climate change are becoming increasingly evident. A warming planet can expect to see stronger hurricanes over time and a higher incidence of more powerful storms. But the total number of storms could drop, as factors like stronger wind shear could prevent weaker storms from forming.
Hurricanes also get wetter due to increased water vapor in the warmer atmosphere; scientists have suggested that storms like Hurricane Harvey in 2017 produced much more rain than they would have had without the human effects on the climate. In addition, rising sea levels contribute to increased storm surges, the most destructive element of tropical cyclones.
A major United Nations climate report released in August warned that countries had delayed cutting fossil fuel emissions for so long that they could no longer prevent global warming from intensifying over the next 30 years, resulting in more frequent life-threatening heat waves and severe droughts. Tropical cyclones have likely become more intense over the past 40 years, according to the report, a change that cannot be explained by natural variability alone.
Ana became the first named storm of the season on May 23, making it the seventh consecutive year that a named storm has developed in the Atlantic Ocean before the season officially begins on June 1.
In May, scientists from the National Oceanic and Atmospheric Administration predicted there would be 13 to 20 named storms this year, of which six to 10 would be hurricanes and three to five major Category 3 or more hurricanes in the Atlantic. In early August, in a mid-season forecast update, they continued to warn that this year’s hurricane season would be above average, suggesting a busy end to the season.
NOAA updated its forecast in early August, forecasting 15 to 21 named storms, including seven to 10 hurricanes, by the end of the season on November 30.
Last year there were 30 named storms, including six major hurricanes, forcing meteorologists to exhaust the alphabet for the second time and use the Greek letters.
It was the highest number of storms on record, exceeding 28 in 2005, and included the second highest number of hurricanes on record.
Jacey fortin, Christophe mele and Daniel Victor contributed reports.