Weird weather, Arctic melt and why the connections matter
Scientists met in Whistler, B.C. recently to better understand how the Arctic is connected to the rest of the world’s climate and weather.
This is a meeting of the brightest minds in the field. The Congress of the Canadian Meteorological and Oceanographic Society jointly held with the American Meteorological Society’s Conference on Polar Meteorology and Oceanography.
So what to do at a meeting with all of this brain power?
I wanted some questions answered for myself. As a meteorologist, I see the wild swings in daily and weekly weather and have always been skeptical about the direct link between parts of our changing climate and specific events of extreme weather.
There’s been a lot of attention recently is the connection between shrinking Arctic sea ice and extreme weather, such as the recent harsh winters in parts of Eastern North America and even Hurricane Sandy.
Arctic warming and the loss of Arctic sea ice is a well-documented trend. Despite the swings from year to year, the overall trend is clear. There is reasonable confidence that we will see a nearly ice-free summertime Arctic ocean in the next 40 years. And this trend is largely the result of human activities: greenhouse gas emissions.
But can we link changes in the Arctic to specific weather events as some research has suggested? Not likely, says Dr. Elizabeth Barnes, an assistant professor at Colorado State University.
Barnes is one of the top young minds in atmospheric science. If you haven’t watched her in the video above, go back and watch it. Barnes has examined whether Arctic warming has significantly influenced the mid-latitude jet stream.
I like to think of the jet stream as the director in the great atmospheric drama that unfolds around the mid-latitudes of the world on a daily and weekly basis. It’s the ups and downs of the jet stream that dictate the storm track, and in turn the extremes in our weather.
Barnes and others have found that the natural variability in the jet stream pattern tends to overwhelm whatever contribution may come from a warming Arctic. This is still an area of active research, but at the very least we should treat any study that tries to directly link Arctic warming to a given weather event or pattern with extreme caution.
If Arctic sea ice loss isn’t affecting our weather, why should we care?
We need to think big picture. Even if changes in the Arctic don’t directly impact the severity of a winter in a southern Canadian city, the global changes taking place are serious.
People are conditioned to look for immediate cause and effect. It’s understandable to want to tie a storm that just hit us to increased greenhouse gases. Most of us have to be forced to plan for the future. This means that critical global issues such as climate change don’t register in our daily lives. Unfortunately, there is a tendency to use the immediate impacts of weather to scare us into action on climate change.
While there is an argument that the ends justify the means, there is danger in this. Jumping on the latest extreme-weather trend and saying that it’s primarily human induced gives ammunition to climate change skeptics when that trend reverses the next year.
Climate change is hard to grasp. We experience the weather. We don’t experience the climate. A warming climate changes the frequencies of certain types of extremes, but the vast majority of what we experience day to day in southern Canada is due to the natural fluctuations of the jet stream – the result of a spinning world and the heating of the sun.
Human-induced global warming is happening and will continue to happen – this is settled. Scientists understand how greenhouse gases contribute to warming. What’s more difficult to determine is how the circulation patterns that drive our weather could change in the future.
Regardless of this uncertainty, we should care about climate change because of the impacts on global sea-level rise and the massive impact expected on hundreds of millions in vulnerable cities and because of acidification of the oceans and the impact on the food chain. The climate will warm and this will have major impacts on agriculture, but the specifics of who will win and who will lose are not clear cut.
It’s important that we communicate the science of climate and weather as clearly and truthfully as possible. And just because we can’t link a given weather event to climate change, doesn’t mean we should throw the baby out with the bathwater.