With named storms coming earlier and more often in warmer waters, the Atlantic hurricane season is going through some changes with meteorologists ditching the Greek alphabet during busy years.
But the Atlantic hurricane season will start this year on June 1 as traditionally scheduled, despite meteorologists discussing the idea of moving it to May 15.
A special World Meteorological Organization committee Wednesday ended the use of Greek letters when the Atlantic runs out of the 21 names for the year, saying the practice was confusing and put too much focus on the Greek letter and not on the dangerous storm it represented. Also, in 2020 with Zeta, Eta and Theta, they sounded so similar it caused problems.
The Greek alphabet had only been used twice in 2005 and nine times last year in a record-shattering hurricane season.
Starting this year, if there are more than 21 Atlantic storms, the next storms will come from a new supplemental list headed by Adria, Braylen, Caridad and Deshawn and ending with Will. There’s a new backup list for the Eastern Pacific that runs from Aidan and Bruna to Zoe.
Meanwhile, the National Oceanic Atmospheric and Administration is recalculating just what constitutes an average hurricane season. If it follows the usual 30-year update model, the new “normal” season would have 19 percent more named storms and major hurricanes. And prominent hurricane experts want meteorologists to rethink how they warn people about wetter, nastier storms in a warming world.
MIT hurricane researcher Kerry Emanuel said “this whole idea of hurricane season should be revisited.”
The National Hurricane Center has already decided to start issuing its routine tropical weather outlooks for the Atlantic on May 15, but after discussion the special WMO committee decided to keep 2021’s hurricane season to its traditional calendar.
“We’re putting together a team” to look at both the storm count and how to warn people best, said hurricane center Director Ken Graham. “I want some data before making this big decision.”
For six straight years, Atlantic storms have been named in May, before the season even begins. During the past nine Atlantic hurricane seasons, seven tropical storms have formed between May 15 and the official June 1 start date. Those have killed at least 20 people, causing about $200 million in damage, according to the WMO.
Last year, the hurricane center issued 36 “special” tropical weather outlooks before June 1, according to center spokesman Dennis Feltgen. Tropical Storms Arthur and Bertha both formed before June 1 near the Carolinas.
Storms seem to be forming earlier because climate change is making the ocean warmer, University of Miami hurricane researcher Brian McNoldy said. Storms need warm water as fuel – at least 79 degrees. Also, better technology and monitoring are identifying and naming weaker storms that may not have been spotted in years past, Feltgen said.
Meteorologists calculate climate averages based on 30-year periods to account for variations in daily weather.
With so much activity, MIT’s Emanuel said the current warnings are too storm-centric, and he wants them more oriented to where people live, warning of specific risks such as floods and wind. That includes changing or ditching the nearly 50-year-old Saffir Simpson scale of rating hurricanes Category 1 to 5.
That wind-based scale is “about a storm, it’s not about you. I want to make it about you, where you are,” he said. “It is about risk. In the end, we are trying to save lives and property,”
Differentiating between tropical storms, hurricanes and extratropical cyclones can be a messaging problem when a system actually has a cold core, because these weaker storms can kill with water surges rather than wind, Emanuel and University of Albany atmospheric scientist Kristen Corbosiero said.
For example, some underestimated 2012’s Sandy because it wasn’t a hurricane and lost its tropical characteristic.