World

Texas snow: Polar vortex turns world’s weather upside down

“Wobble” in one of the world’s most important meteorological engines has caused confusion and death, with snow falling in rarely seen places and temperatures -12 ° C in Texas.

The “wobble” of the weather has upset parts of the world’s climate, leading to a strange situation in Texas that is twice as cold as Alaska.

Meanwhile, in Europe, snow covered the world-famous Parthenon in Athens as temperatures fell below freezing on Tuesday. The Greek capital can usually rely on mild winters, but in the northern part of the country there are places where mercury can reach -20 ° C.

North America weather A huge lick of freezing polar air descends south, even bringing snow to northern Mexico.

A continental temperature anomaly map from the University of Maine’s Institute for Climate Change reveals a unique situation.

Temperatures on February 15 were more than 20 degrees Celsius below average across Texas, and Greenland and the North Pole were partially above average 10 degrees Celsius.

But far from being a sign of climate change, there is a lot of heat, and meteorologists say the current situation is caused by unusually warm temperatures in the Arctic.

Relation: Wet Australian summer continues

More than 20 people have now died during the cold weather, with car accidents mainly in states such as Texas, Kentucky and Missouri, according to news agency AFP.

In Texas, where the freeze forced energy companies to carry out a power outage, women and girls died of carbon monoxide poisoning after using their cars to generate heat, according to NBC News.

A homeless man was killed “probably by exposure” in Houston on Monday, according to local police. A Louisiana man died when he slipped on ice and hit his head, and a 10-year-old Tennessee boy died on Sunday after he and his 6-year-old sister fell through the ice into a pond. ..

President Joe Biden vowed to provide additional emergency resources to those affected by the “historic storm” on Tuesday. According to a White House statement, he also thanked “road workers, highway patrol officers, and first responders who are taking swift action in horrific situations to save lives.”

Relation: Scientists puzzle the strange weather in Australia

POLAR VORTEX’WOBBLE’

Austin, the capital of Texas, is a city where the normal February minimum temperature is around 7 degrees below freezing, with temperatures dropping to -12 degrees. Anchorage, the capital of Alaska, was milder than that, down to just -6C.

The National Oceanic and Atmospheric Administration (NOAA) predicted many bone chills earlier this month.

It dropped the fiercely cold weather into three events.There La Nina Climate DriverThis also brought a rainy winter on the east coast of Australia. In addition, there were optimal atmospheric conditions to allow cold air to penetrate south, and the third was the weakening of the polar vortex.

“These three reasons are not independent. Instead, they interact and interact like three different colored food dyes swirling in a glass of water,” NOAA said. Says.

Scientists at the Monash Climate Change Communication Research Hub (MCCCRH) in Melbourne said polar vortex is the most root cause.

“The polar vortex is a large area of ​​cyclones and cold air above the Arctic,” MCCCRH said in a news.com.au report on the situation in the United States.

“It’s related to jet streams. Jet streams are a powerful band of wind that carries moisture, moving a mass of cold, warm air and storm systems along its path.

“When the jet stream weakens, it becomes” rippling “, allowing very cold air to squeeze south and warm air to be pushed north elsewhere. “

This “wobble” of the jet stream is due to changes in Arctic temperature, the report said.

Arctic temperatures are usually much lower than Texas temperatures. This is not surprising.

It is this contrast that keeps the jet stream moving very nicely around North America, Northern Europe and Asia. However, as the temperature contrast between the poles and mid-latitudes weakens, the jet stream weakens and begins to deviate from the quilter.

“The Arctic is warming faster than the rest of the globe, and research shows that this warming weakens the jet stream, meanders north and south, and releases frigid air away from the poles. It has been suggested.

“The” wobbling “of polar vortices can bring much colder air to Europe, Asia, and the United States than normal air,” said MCCCRH.

Stratosphere A sudden surge in temperature struck the polar stratosphere (a zone 10-50 km from the surface of the planet), which probably triggered the weakening of polar vortices and jet streams.

“There are clear warming trends around the world, but regional meteorological systems vary by location and time,” said Dr. James Goldie of Monash University.

Freezing due to global warming

But the whole story could be Texas sub-zero temperatures, which could have been much colder.

Climate Central is a climate science information service based in the United States. A survey of 244 locations in the United States, including Texas, found that 98% recorded higher annual temperatures.

For example, the lowest average temperature in Minneapolis in the early 1970s was about -32 ° C. However, by the late 2010s, -26C was by far the normal lowest temperature.

In Austin, Texas, half a century ago, mercury sank 13 degrees lower than it does today during the coldest months of the year.

“Yes, this polar outbreak is extreme, terribly cold and breaking records,” Climate Central’s chief meteorologist Bernadette Woods Placky told news.com.au.

“But what we found is that many of these temperatures are still cold, but the cold wasn’t as cold as it used to be, both in intensity and frequency.

“In addition, the record highs set in the United States are well above the record lows.”

Texas snow: Polar vortex turns world’s weather upside down Source link Texas snow: Polar vortex turns world’s weather upside down

Back to top button