PRI: The Link Between Severe Winters and Climate Change

Climate-change skeptics point to a severe winter, long stretches of below-average temperatures and a so-called “bomb cyclone” as confirming that average rising temperatures may not be a problem. PRI’s Carolyn Beeler reports that the term “bomb cyclone” refers to an intense course caused by a quick drop in atmospheric pressure. But the icy weather reaching far beyond the Arctic confirms a scientific theory suggesting that climate change is weakening the Earth’s jet streams, the narrow bands of wind in the upper layers of the atmosphere that “can be thought of as the boundary between the warm air of the tropics and the cold air” of the Earth’s poles,” explains Beeler. Strong temperature differences maintain the jet streams. While virtually all climate scientists agree that climate change is underway and the rising average global temperatures are a threat, they do disagree about the reasons for the weakening jet streams: “One camp attributes the cool temperatures to natural variation in global weather systems,” she writes. “But there’s a growing body of evidence suggesting that climate change may be fueling wavy jet streams and contributing to the trend.” The jet streams moderate weather, reducing volatility that disrupts the agriculture industry and other parts of the economy. Other studies examine disruptions to the polar vortex, a rotating low-pressure zone at both of the earth’s poles. – YaleGlobal