- Of the 30 storms, 12 hit the US coast, also a record number. The previous record was 9.
- October and November were extremely active with seven storms and a whopping 4 major hurricanes.
- In the United States, Hanna, Laura and Zeta all quickly escalated in the 24 hours before they landed.
It’s officially over.
After six long months and 30 storms from Arthur to Iota, the record-breaking Atlantic hurricane season ends on Monday.
“I didn’t think I would live to see this, but it happened,” Penn State University meteorologist Michael Mann told USA TODAY, referring to the record number of named storms in a single season.
A typical season sees only 12 storms.
All the preseason forecasts indicated that an active season was likely, but none came close to the actual number. “Our group here at Penn State predicted an exceptionally active season, up to 24 named storms – most preseason predictions,” Mann said. “But even THIS wasn’t an aggressive enough forecast.
Of the 30 storms, 12 hit the US coast, also a record number. The previous record was nine, raised in 1916.
It was the fifth season in a row with above-normal activity, the National Oceanic and Atmospheric Administration said. There have been 18 above-par seasons out of the last 26.
“I think what really stood out for me in 2020 is the extremely active end of the season,” said a Colorado State University hurricane researcher. Phil Klotzbach. “October and November were extremely active with seven storms and four major hurricanes (Delta, Epsilon, Eta and Iota).”
Prior to this year, Klotzbach said, no October-November had more than two large hurricane formations.
Although the official end of the hurricane season is Monday, storms can develop in December. Meteorologists from the National Hurricane Center on Sunday monitored an area of low pressure in the far eastern Atlantic Ocean for possible subtropical development. If the area becomes a named storm, it would be called Kappa, the 31st named storm of the season.
Tropical storms and hurricanes in December are extremely rare. “A single recorded season has had more than one named storm form in December, and this dates back to 1887,” Klotzbach said.
When will it end? When will this relentless hurricane season in the Atlantic finally end?
A marked rapid intensification this season
A major hurricane has wind speeds of at least 111 mph and reaches Category 3, 4, or 5 on the Saffir-Simpson hurricane intensity scale.
Eta and Iota crashed in Central America as Category 4 storms in November, causing hundreds of deaths and widespread misery and destruction. Iota was briefly a Category 5 before weakening and hitting Earth as a Cat 4.
“One of the most notable features of 2020 has been all of the intensifying (and often rapidly escalating) hurricanes we have experienced up to the point of disembarkation,” Klotzbach told USA TODAY. “Particularly for the United States, Hanna, Laura and Zeta all quickly escalated in the 24 hours before they landed.”
Rapid build-up is generally defined as boosting over 35 mph in 24 hours. This season, winds from several storms have increased by 50 mph or more in 24 hours.
Predicting escalation, especially rapid escalation, is a challenge and a nightmare for meteorologists trying to advise emergency managers on evacuation decisions.
The 2020 season started early when Arthur trained on May 16. The extremely active season quickly went through the predetermined list of 21 names, ending with Wilfred on September 18. Then, for only the second time in history, the Greek alphabet was used for the rest. of the season as Alpha formed on the same day. Nine letters of the Greek alphabet have been used, up to Iota.
Laura was America’s deadliest hurricane of the season. The storm killed at least 40 people after roaring in Louisiana on August 27 with winds of 150 mph. It was also the most destructive, causing at least $ 14 billion in damage to the United States.
Climate change is a factor, expert says
Causes of the active year, according to NOAA’s senior seasonal hurricane forecaster Gerry Bell, included warmer-than-average Atlantic sea surface temperatures and a stronger monsoon in West Africa. , as well as wind patterns from Africa which were more favorable to the development of storms.
“These conditions, combined at La Niña, helped make this extremely active and record hurricane season possible,” said Bell.
La Niña, a natural cooling of ocean water in the Pacific that emerged this fall, is more hurricane-friendly because it reduces wind shear in the Atlantic, which acts to crush budding tropical cyclones.
‘Past a point of no return’:Cutting greenhouse gas emissions to zero still won’t stop global warming, study finds
Mann of Penn State said climate change played a role in the active year: “The main ingredient in our forecast was the unusual warmth of the tropical Atlantic Ocean, and the heat of the oceans cannot be explained without taking into account the warming effect of increased carbon dioxide concentrations in the atmosphere from the combustion of fossil fuels.
“A warmer ocean surface appears to favor more storms, but just as important, it means more energy to escalate tropical storms into major hurricanes, including Category 5 monsters like Iota,” he said.
Mann said that in recent years, when the world’s oceans were at their warmest, “we have witnessed the most severe hurricanes on record, in the northern and southern hemispheres. And the seasonal window in which the oceans are sufficiently warm. hot to produce hurricanes thrive. “
In addition to stronger storms, climate change could mean more precipitation as warm air contains more water vapor.
Contributor: Kimberly Miller, The Palm Beach Post
