Cold and wet—no more global warming?

Photo: The Boardman River covered the riverfront boardwalk in Traverse City in May as water levels rose across the state to near record heights.

By Linda Alice Dewey

Sun contributor

Our weather this year has been downright chilly and wet, so we won’t hear anything more about global warming, right? Not necessarily, scientists say. The key to the answer is in the term, “global.” You have to look at how temperatures average over the globe. 

Let’s look at 2019 so far. Our extremely cold winter was outbalanced by simultaneous record-breaking heat in Australia. Meanwhile, the Arctic continues to be warmer than normal. That affects everything above the equator.

While we complained over our cold, wet weather which continued into June, San Francisco sweltered in temperatures over 100, Hawaii experienced its 10th hottest June day in a row on June 25, the Southeast was in the grips of its own heat wave, and temperatures in India soared over 120 degrees, killing 36. Finally, an end of June heat wave swooped down over Europe with France, especially, preparing for its own record-breaking heat. 

Our unusual cold weather, by the way, is actually caused by global warming. Sounds crazy, right? Here’s how it works, as explained by astrophysicist Ethan Siegel, Ph.D in an aptly named article, “This is why global warming is responsible for freezing temperatures across the U.S.” 

He writes, “A warmer Earth makes sudden stratospheric warming events more likely and more frequent. And those events destabilize the polar vortex, bring cold air down into the mid-latitudes, and cause the extreme weather we’re experiencing right now.”

Remember our harsh weather earlier this year, beginning in January and into February? Meteorologists called it “Polar Vortex 2019.” But the Polar Vortex has always existed. It’s a mass of air stationed over the Arctic. What changed is that it broke apart! Then part of it moved down our way, causing this weather event, and they gave it that name. 

What made it move? Warming nearby air up at the Arctic. Basically, when it’s super cold here, explains Michigan State University doctoral student Lukas Bell-Dereske, it’s super warm in the Arctic. 

Last fall, the vortex was pushed by that warming air into cooling fall Siberian air. This caused a huge disruption.  

“The disruption in this counterclockwise-spinning beast,” predicted science journalist Tom Metcalfe for Live Science in January, “called the ‘polar vortex,’ ­is thought to be caused in part by a warm summer over the Arctic and a relatively cold fall over Siberia. The result for the United States and northern Europe? A severe winter lasting throughout February and possibly into March.” This prediction certainly proved true forLeelanau County. Try all the way into June! 

On June 25, MLive meteorologist Mark Torregrossa reported that one piece of the vortex had sagged down and hovered over us this spring. He states, “The Polar Vortex has been disrupted and broken into several pieces for the last few months. Now the piece of the Polar Vortex that has been dominating our weather in the eastern third of the U.S. is going to shift north. This northward shift should bring summer back.” He predicts we will have summer for a few weeks, then the vortex may return, but only for a few days.

Here’s the point. The extreme weather we have experienced over the past several years—simultaneous hot and cold temps at different places on the planet resulting in increased incidents of floods and droughts, hurricanes and wildfires—is the hallmark of global warming. Averaged out, it raises the annual average planetary temperature, as we see happening in 2019, even with the cold winter and spring here in Leelanau County and across the Midwest. 

With that cold comes precipitation, as Bell-Dereske told the Sun five years ago in an article entitled, “How climate change will affect the Sleeping Bear Dunes.” 

“Critical for Sleeping Bear,” he says, “scientists predict more potentially damaging heavy rain events during the northern Michigan growing season, May 15-Sept. 15. A recent Intergovernmental Panel on Climate Change report predicts that precipitation will increase by more than 3 percent for every 1 degree (Celcius) change in temperature. A global temperature rise by 3-5 degrees by 2100, could mean a 20-40 percent increase in spring and summer precipitation in Leelanau County.”