This winter has been one of extremes. Here in the mid-Atlantic, a near-tropical holiday season was followed by a record-setting blizzard, and just this past weekend, practically arctic temperatures put a damper on Valentine’s Day– or at least, probably inspired more people to have their celebrations at home by the fire.
These outrageous extremes aren’t new to this year. 2014 and 2015 also had winters that careened between unseasonable warmth and severe freezing temperatures, even in areas known for milder winters. What’s goin’ on? Well, to put it very, very simply, you can blame climate change. But the answer is a lot more complex-and has far bigger consequences than frozen pipes and icy sidewalks. Allow us to re-introduce our old friend, the polar vortex:
The polar vortex, a rotating current of supercold air, normally stays up near the Arctic Circle. But the polar vortex is stabilized by the temperature difference between the North Pole and areas closer to the equator. This difference in temperature also creates a difference in pressure, which corrals all that icy air up north.
The trouble starts when temperatures in the north and in the south get closer together—and climate change is warming the Arctic faster than any other part of the world. When that happens, the stability between the air masses breaks down, allowing the polar vortex to bulge southward–pummeling everything in its path with below-zero weather, snowstorms and punishing wind chill.
So what does that mean for wildlife? Well, unusually cold temperatures can certainly be hard on southern species that aren’t used to it. Fortunately most polar vortex events only last a few days. But there’s a bigger story here. More frequent visits from the polar vortex are partly caused by (and may be one of many symptoms of) our warming planet, causing trouble for people and wildlife alike. And as things heat up, drought, hurricanes, wildfires and floods are all expected to become more frequent too. In the case of drought and wildfires, there’s a lot of evidence that they already have.
The effects of climate change on wildlife cannot be overstated, and the pressure’s rising every year. Bumblebees are being squeezed out of their southern ranges in Europe but aren’t moving further north to compensate. Corals are dying as their water gets too warm to survive, and ocean acidification from increased carbon dioxide in the atmosphere makes it harder for mollusks like oysters to form strong shells as they grow. These species are being squeezed in a climate vise, and only lowering emissions and reducing the CO2 concentration in the atmosphere will slow the effects.
Other species have freedom to move when the going gets tough, but time isn’t on their side. Snowshoe hares aren’t timing their transition to their white winter coats correctly-turning them into fluffy white targets on a brown earthy background for lynx (which are also affected by climate change), hawks and other predators. Polar bears face shorter and shorter hunting seasons as Arctic summers get warmer and the sea ice they need for catching seal melts faster.
All of these species and more face an unknown future as global temperatures continue to rise. And paradoxical as it may seem, the warmer it gets, the more likely we are to experience freezing arctic blasts from the polar vortex each winter.
So what can we do to help climate-affected wildlife? First of all, we must continue the global push to get carbon emissions under control. The Paris Conference and the subsequent international climate agreement that came from it are a great start, but we still need a comprehensive, worldwide solution for cutting emissions and transitioning to sustainable energy. This urgent need makes the Supreme Court’s recent delay of the Clean Power Plan all the more ill-advised. Here in the United States, we need to make sure wildlife habitat is as rich and resilient as possible. Climate change affects habitat quality and food availability for many species, so ensuring that all of our native species have room to move in a landscape that supports them is crucial.
The polar vortex serves as an important reminder that climate change doesn’t just mean hot weather: it means more extreme highs and lows, destructive weather and natural events like fire and flood, and conditions that make it tougher for wildlife to survive. But the answer to all of these issues are the same: if we want to make our planet a better place for wildlife, and to keep that arctic air up north where it belongs, we have some serious work to do on the global climate.
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