By MOOK Scenic Spots House, compiled and reported
In recent years, environmental pollution has led to ozone layer depletion, triggering global warming and causing drastic climate changes across the planet. Global warming, rising sea levels, El Niño, and La Niña phenomena have all resulted in severe disasters. Now, due to polar oscillation, even the central and western parts of the United States have experienced temperatures as low as minus 52 degrees.
Lake Michigan in the U.S. has completely frozen over due to extreme weather. (Photo/World Journal with Xiang Xian, same below)
From a scientific perspective, polar oscillation is also known as polar overturning. When it occurs in the Northern Hemisphere, it's called the Arctic Oscillation, referring to the inverse pressure relationship between the Arctic and the mid-latitude regions of the Northern Hemisphere. When it occurs in the Southern Hemisphere, it's called the Antarctic Oscillation.
Niagara Falls frozen solid by frigid air masses.
When the Arctic Oscillation index is positive, it indicates lower atmospheric pressure in the Arctic and greater pressure differences in the mid-latitudes. This strengthens the polar vortex surrounding the Arctic, which can suppress the southward movement of Arctic cold air, leading to warmer temperatures in the central U.S. and Eurasian continent — commonly referred to as a warm winter. Conversely, a negative index results in a significant temperature drop.
Diagram of Arctic Oscillation.
Currently, the Arctic region is warming at more than twice the rate of other parts of the Earth, creating the Arctic amplification effect. As a result, temperature plunges in mid-latitude regions during winter become particularly pronounced.
Mid-latitude regions entirely blanketed in white.
When warm air enters the Arctic Circle and weakens the polar vortex that normally traps cold air, the cold air shifts southward to the Eurasian and North American continents, resulting in an unprecedentedly harsh freeze. In the central and western U.S., temperatures even dropped to minus 52 degrees.
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