Experts: Everything points to another tense hurricane season

Kill the hatches for the next nasty hurricane season. Almost every natural force and a bunch of human -…

Kill the hatches for the next nasty hurricane season.

Almost every natural force and pile of man-made – more than just climate change – have turned the last few seasons of hurricanes in the Atlantic into deadly and costly wild ones. The season, which begins on Wednesday, looks like another note in the record refrain because all of these ingredients for the disaster are still valid, experts warn.

These factors are said to show but do not promise more trouble: the natural climate event of La Nino, human-induced climate change, warmer ocean waters, deep hot currents in the Gulf of Mexico, intensifying storms in Africa, clearer skies, decades of active cycle and the massive development of property along the coast.

“It’s all a kitchen sink,” said Phil Klotzbach, a hurricane researcher at the University of Colorado.

Over the past two years, weather forecasters have run out of storm names. It was an expensive gallery of major hurricanes – with winds of at least 111 miles per hour (179 kilometers per hour) – that hit the earth over the past five years: Harvey, Irma, Maria, Florence, Michael, Dorian, Umberto, Laura, Teddy, Delta , Zeta, Eta, Iota, Grace and Ida.

“This is a pattern we have been trapped in. And what statistics to think about: from 2017 to 2021, more categories 4 and 5 (hurricanes) hit the US land than from 1963 to 2016, “- said the director of the National Hurricane Center Ken Graham in an interview with the Associated Press before the two hurricane hunters. planes flying in storms.

Graham, echoing most experts and every pre-season forecast, said “we have another busy one”. Last year, the Atlantic set a record for six seasons of hurricanes above average, breaking the old record – three in a row, and forecasters predict the seventh.

The only opposite sign is that for the first time since 2014, the storm did not form until the official start of the hurricane season on June 1, but forecasters are watching a record hurricane “Agatha” in the eastern Pacific, which is likely to pass over land and reform as Alex in the Gulf of Mexico later this week.

Here’s what could make the Atlantic chaotic this season:

LA NINA

One of the biggest effects of hurricane seasons in the Atlantic occurs in the hemisphere in the temporarily cooling waters of the equatorial Pacific, a natural cyclical phenomenon called La Nino, more dangerous to the United States the other side of El Niño.

La Nina is changing weather around the world, including making hurricanes more likely in the Atlantic. It begins in the Sahel region of Africa, where the seeds of many of the strongest hurricanes of the middle season, called the capes of Cape Verde, are formed. Often the dry area in La Niña is wet and turbulent, which promotes early formation.

One feature of the weather that can decapitate storms or prevent them from forming are strong cross winds called shear. But La Nina is largely stifling the shift, which is a “huge factor” to boost storm activity, said Kristen Carbasiero, a hurricane researcher at the University of Albany.

CLIMATE CHANGE

Studies show that climate change makes hurricanes wetter because warm air can hold more moisture, and the strongest storms become stronger. Storms can also stop longer, allowing them to rain more in the same place as Harvey in 2017, where more than 50 inches (127 centimeters) fell in one place. They are also rapidly increasing, experts say.

While studies show an increase in the number of severe storms due to human-induced climate change, scientists still disagree on what global warming means for the overall frequency of all storms. Some scientists see a slight decrease due to fewer weaker storms, but others, such as Hurricane Hurricane researcher Kerry Emanuel, see an overall increase in total storms.

Emanuel’s study found an overall increase in the Atlantic storm over 150 years, with some exceptions. This increase is too large to be directly related to climate change, Emanuel said, “but it may be indirectly linked to climate change,” especially when global warming changes the rate of ocean circulation is expected.

WARMER WATER

Warm water acts as fuel for hurricanes. Storms cannot form until the water temperature reaches 79 degrees (26 degrees Celsius), and the deeper the warm water reaches and the higher its temperature, the more the hurricane has to feed.

And because of climate change and natural weather changes, water in much of the Atlantic, Caribbean and Gulf of Mexico is warm and attractive to storms, said University of Miami hurricane researcher Brian McNoldy. According to seasonal hurricane weather forecaster Matthew Rosencrans, in a key area of ​​storm formation the water is about half a degree warmer (0.3 degrees Celsius) than last year at this time of year.

CURRENT LOOP

In the Gulf of Mexico, there is a common phenomenon called Loop Flow, when warm water flows extremely deep. This is important because hurricanes usually bring cold deep water when they pass over warm water, and this limits their strengthening. But Loop Current often turbocharges storms, and it spills vortices of warm deep water across the bay to intensify the storm.

This year, the flow of the loop seems particularly strong, northern and disturbing, according to Emanuel and other experts. They compared it to Loop Current, which activated Camilla in 1969, Katrina in 2005 and Ida last year.

McNoldy said Monday’s Loop current was 1.8 degrees (1 degree Celsius) warmer than usual.

MORE CLEAN AIR

Traditional air pollution from factories and cars – dirty air from smog and fine particles – reflects sunlight and cools the atmosphere, scientists say. This cooling effect from air pollution probably helped reduce the number of storms in the 1970s and 1980s, which were a quiet period in the Atlantic.

But as Europe and the United States cleared most of the air pollution, the Atlantic during the hurricane season became more stormy, while in Asia, where air pollution is on the rise, a new study says. Experts say reducing air pollution and increasing storms in the Atlantic are likely to be a permanent condition.

LONG TERM CYCLES

Hurricane researchers have noticed for more than a century or so a type of storm activity cycle on and off with about 20-30 years of intense hurricane seasons in the Atlantic and then 20-30 years less activity. The current intense cycle began in 1995 and should theoretically end soon, but scientists have yet to see signs of this.

The theory behind the cycle is related to ocean currents, salinity and other natural cycles on a global scale. But recently, some scientists have begun to question how serious a factor a cycle can be, and whether air pollution is true, and now climate change is changing the cycle.

DEVELOPMENT

In addition to all these weather factors people have a problem. During the lull in thunderstorms in the 1970s and 1980s, air conditioning in the south became more common and storms were in the depths of consciousness, so more people moved and built in storm-prone areas, said former NOAA scientist Jim Cosin, now a risk company The Climate Service.

But the storms returned when the pollution disappeared and when climate change worsened. Add La Ninas, insurance that facilitates recovery in dangerous areas, “and now we’re paying for the fever” with a growing and severe storm and more people and buildings at risk, ”Cosin said.

For at least the next five years, Kosin said, “we need to fasten.”

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