For many people, especially those living in the South, the Arctic epidemic that has plagued the heart of the country in the past week is a cold that has occurred in only a century. Set countless record low temperatures.HappeningThis , Cut off electricity for millions of people and destroyed water pipes, .
However, in the past ten years, as climate change has generally warmed the winter, the number of global heat records is 2 to 1 more than the number of cold records. This historical cold wave seems counterintuitive. It is not. In fact, paradoxically, climate warming may actually cause extreme cold.
In the past few decades, meteorological science has made great strides so that meteorologistsA few weeks in advance. This is because this extreme pattern is triggered by a huge, recognizable phenomenon that broke out in the Arctic at the beginning of the year, known as “stratospheric warming”
CBS News previews severe winter weather hereHe explained that in just a few days in late December and early January, the high-altitude atmosphere above the North Pole increased by 100 degrees Fahrenheit-from minus 110 degrees Fahrenheit to minus 10 degrees.
SSW is a natural occurrence, occurring every few winters, heralding extreme weather in the following weeks. This is because when the Arctic heats up rapidly, it destroys the semi-permanent weather system that is present every winter in a large amount of rotating cold air-the polar vortex.
Usually, the jet flows around the vortex and acts as a variety of nooses, keeping cold air inside. However, when the Arctic warms, the jet will weaken and stretch, causing cold air to pour south.
This created a vast range of warm air mountains over the Arctic, temporarily replacing the cold vortex. The warm mountains act as the atmosphere, redirecting jets and bitter cold air to the south.
Although this bitter air conditioning is undoubtedly unforgettable for the upper half of the Midwest, it is not unusual for them.The record set as early as 1899 is more extensive and severe in the northern part of the United States
What makes this special situation history is that the core of the cold air (part of the polar vortex) has plummeted farther south than ever before: a full 4,000 miles from ordinary houses near the North Pole.
As a result, hundreds of daily minimum records were set in the past week, mainly in the central and southern plain states. Dozens of unprecedented records have also been set as unprecedentedly ruthless towns, they are not used to and are not prepared for the explosion of suffering. The following animation loop displays monthly records with dark blue dots and historical records with black dots.
This produced some amazing visual effects. Frozen waterfall in the Ozarks of Arkansas.
There are also frozen swamps in Louisiana.
Although the long-term trend is that the winter throughout the United States has been warming and the cold is gradually reducing, this situation has emerged. In Minneapolis-St. Paul (Paul), for example, from 1970 to 2020, the coldest temperature of the year rose by 12.1 degrees Fahrenheit.
The recent extreme weather is not limited to the United States. When the jet flow in a region is extreme, it is usually extreme on a global scale. In Saudi Arabia, snowy camels create a rare but not unheard of sight.
In Jerusalem and parts of Jordan and Syria, while record-breaking heat affects other parts of the Middle East, such as Iraq, winter temperatures soar to 93 degrees.
The relationship between extreme cold and extreme heat
Although this extreme cold and extreme high temperature may seem strange, it is actually what meteorologists expect from a wave-like jet. Think of it this way: what goes up must go down. When the atmosphere forces cold air to move south, there must be an equal and opposite reaction that forces warm air to move north. When air quality is lost to places where they usually don’t go, extreme weather and its impact on society follow.
Many climate scientists believe that not only can climate change cause a sudden warming of the stratosphere, but climate change itself may also have a similar effect in the Arctic, because it has also caused significant warming. Due to man-made climate change,It is three times the global average.
The wave-like jet theory is related to climate change and was first proposed by Dr. Jennifer Francis of the Woodwell Climate Research Center. The theory has a logical meaning: a warming Arctic will reduce the gradient between cold and warm air, thereby weakening the temperature contrast mechanism that powers the jet. This results in a weaker wave-shaped jet, which is more likely to cause cold air to overflow south.
This theory has been adopted by many other climate scientists who believe that obvious extreme phenomena (such as the recent explosive explosion) are signs that the theory is worthy of proof.But quite a few other scientists are concerned about climate change andOn the jet stream.
Part of the reason is that the atmosphere is very noisy, and climate models cannot yet reproduce the details of complex systems. Therefore, finding evidence to finally prove or refute this theory has always been a challenge. But many long-term meteorologists believe that the logic, research and qualitative evidence they have observed is sufficient to prove this.
All meteorologists and climate scientists can agree that this extreme event is caused by a sudden warming of the stratosphere. That’s motivation.
For those who are tired of the cold and heavy snow, this is good news: the extreme mode seems to be gradually developing. The earth will return to its normal state. Before we enter the spring, this does not rule out the outbreak of cold air and snowstorms in the United States, but it should restore the weather to a certain degree of normality.