Over the past few weeks, a disastrous winter storm swept across the United States and Canada. With ice on the side of roads in Seattle, snow everywhere in the Midwest, and a snowstorm killing dozens in Buffalo, the situation keeps getting worse.
As the Earth becomes warmer, everything changes. The droughts are getting longer, the heat waves are getting hotter, there are large-scale floods across the world, and clearly, the snowstorms are getting bigger. The connection between powerful winter storms and climate change becomes more evident every day.
During the past few years, the winter season has been getting warmer. Since 1896, average winter temperatures across the contiguous 48 states have increased by nearly 3°F. Spring temperatures have increased by about 2°F, while summer and fall temperatures have increased by about 1.5°F. In all of this, one trend is clear: temperatures have been rising.
Scientifically speaking, then, how did this storm happen?
Some meteorologists believe that the cause of the winter storm was a polar vortex. A polar vortex is a large portion of an area of low pressure and cold air around the North and South Poles. While they have always existed, they get weaker in the summer and stronger in the winter. When the vortex reached the United States, the colder air invaded the warmer air pockets, causing the temperature to drop. This change provokes the “deep freeze” throughout the United States, while the change in air pressure makes the winds stronger. The cause of this storm is believed to be rapid temperature increases in the Arctic. The Arctic has gotten over 5 degrees Fahrenheit warmer since 1979. Compared to the average global rate, the Arctic has gotten warmer four times faster since then.
Scientists believe that the difference between the temperatures at the poles and the temperatures in more tropical areas gets smaller, as the Arctic gets warmer. This causes the polar jet stream, a belt of powerful upper-level winds that sits on the polar front, to get weaker, which further allows the polar vortex, consequently, the storm, to spread.
Climate change has gradually caused an increase in temperatures, resulting in unprecedented natural disasters across the globe.