Wacky weather is being caused by a jet stream shift, according to a new study that connects rapidly warming Arctic regions with unusual weather patterns. Professor Jennifer Francis of Rutger University’s Institute of Marine and Coastal Sciences theorizes that as the colder air of the Arctic warms and becomes closer to the average temperature of the rest of the world, the difference in pressure will roughly equalize, sapping the strength of the powerful wind that drives the jet stream and, by extension, weather across the globe. This results in changes in annual weather patterns and allows systems of high and low pressure to move to places they are usually unable to access as well as hang around in places they usually just skim over. We have seen this with the recent polar vortex and current snowy conditions in Southern states and the warm weather in Alaska.
Although average temperatures have been rising all over the world for several years, the North and South Poles have seen increases almost triple that of areas closer to the equator. Most of the heat generated comes from the oceans that have recently lost their insulating cover of ice, allowing all of the heat trapped in the oceans to rise into the air, raising ambient temperature and bringing the average global temperature closer to equilibrium between the poles and equator. Although the shift has been going for about 15 years, it is still too early to tell if it is the result of man or a natural change in the Earth’s cycle, but the jet stream shift promises wacky weather no matter what the cause. As weather patterns across the globe become stranger and more extreme, relying on information about weather from the past will become increasingly difficult as old patterns become more obsolete.
The jet stream used to be fairly predictable, with harsh or mild winters spotted and prepared for by observing how fast the winds were moving, how warm they were and how much moisture they were carrying. With the ongoing changes taking place now, even the fiercest, snowiest, most unexpected winters of the past may begin to pale in comparison to common weather as warmer, wetter air becomes the norm. As the jet stream continues to slow and become more twisted, rather than the normal straight, fast path it has taken in the past, weather systems could grow more powerful and stay in one place longer by virtue of air being able to accumulate and eddy in one place rather than being shuffled along by currents. The changes going on now are small and slow moving, but as time passes their effects are expected to be felt more strongly with each seasonal cycle to Earth.
With cold weather moving closer to the equator, and warm weather closer to the poles, the shifting jet stream will either begin to stabilize and bring about a new balance, or the weather has started down a slippery slope that will not have a predictable outcome. Although the jet stream shift promises wacky weather in the near future, the truth is, human have not been observing long enough to make an educated guess about the long-term effects of this weather pattern.
By Daniel O’Brien