Global Warming and Extreme Cold: How One Leads to the Other

jfrancis0110weather

Research on the connection between extreme weather – such as the severe cold snap that hit the US Northeast – and global warming, shows that these are intimately connected, despite what climate deniers such as President Trump say

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Story Transcript

GREGORY WILPERT: Welcome to The Real News Network. I’m Gregory Wilpert coming to you from Quito, Ecuador.

It’s official: 2017 was the costliest year on record for weather and climate disasters in the U.S., exceeding $300 billion. This shatters the previous U.S. annual record cost of $214.8 billion established in 2005 due to the impacts of Hurricanes Dennis, Katrina, Rita, and Wilma. This is according to a new report by the National Oceanic and Atmospheric Administration.

2018 began with a bang as the Northeast was hit with a powerful blizzard and brutal, dangerous cold gripped North America’s East Coast. From northern Florida up through New York City and into New England, tens of millions of people were exposed to extreme wind chill and freeze warnings. At least 18 people died as a result of the extreme weather.

States of emergency were in effect in Florida, Georgia, North Carolina, and Virginia as this so-called bomb cyclone snowstorm hit the East Coast with 70-miles-per-hour winds and more than 15 inches of snow in some areas and terrifying flooding hit Massachusetts. In Tallahassee, Florida, residents saw snow for the first time in more than three decades, and frozen iguanas fell from the trees.

While many news meteorologists discussed the polar vortex and a cold front coming from the Atlantic, from the Arctic actually, few mentioned the impact that a warming Arctic due to climate change has.

With us to discuss the recent extreme cold weather in the context of climate change is Dr. Jennifer Francis. She is an atmospheric scientist and professor at Rutgers University’s Institute of Marine and Coastal Studies. She’s the author of the groundbreaking study, “Amplified Arctic warming and mid‐latitude weather: new perspectives on emerging connections.” Thanks for joining us today, Dr. Francis.

J. FRANCIS: Happy to be here.

GREGORY WILPERT: We heard a lot of talk in weather reports about the polar vortex and the jet stream. Please explain to us these phenomena and the role they are playing in the current deep freeze in the eastern United States.

J. FRANCIS: Sure. Well, we probably need to do a little jet stream 101 so people can understand why this affects their weather so much. Everyone’s seen TV weather forecasts and probably seen the jet stream shown on the map of the United States or North America, and basically the jet stream is a river of fast moving air high up over our heads at an altitude up where jets fly, and that’s why it gets its name. The jet stream is there because the Arctic is so cold, and it’s much warmer to the south. This big temperature difference between the Arctic and down here where we all live is really what creates the jet stream in the first place. So the jet stream actually exists at the boundary between that cold air and the warm air to the south.

The jet stream travels around the northern hemisphere, again, this river of fast moving wind, and it has these big north-south waves in it. By separating that cold air to the north from the warm air to the south, if the jet stream is south of you then, you’ll be in the cold air. And the opposite is true if it’s north of you. Well, those waves in the jet stream are actually what create the stormy weather and the nice weather that we experience from time to time. So what you might surmise, then, is that whatever’s going on with the jet stream around you is really what’s controlling your weather. So anything that affects the jet stream, then, is also going to affect your weather.

Now, what is the polar vortex? Well, people have been using that term a little bit loosely lately. It sounds really kind of bad. A vortex kind of gets people thinking about getting sucked down a hole or something like that. But actually, the real polar vortex exists much higher up in the atmosphere above the jet stream, up in a part of the atmosphere we call the stratosphere. In the wintertime, these two things do kind of communicate with each other, so sometimes when the jet stream is very wavy, when there are these big north-south swings in it, it will send some of that wave energy up to the polar vortex, and it will sometimes even disrupt it. It’ll break it down.

If we think about the jet stream in relation to what we’re observing in the Arctic then, we know that the Arctic is warming at least twice as fast as anywhere else on the planet. We know that the sea ice is disappearing rapidly. In fact, in the last 30 years alone, we’ve lost half of the sea ice coverage in the Arctic Ocean. That’s a lot of ice lost in a very short time.

This warming of the Arctic is a big deal because if you think back to what I described as what’s forming the jet stream, because the Arctic is warming so fast, it’s making that temperature difference between the Arctic and areas farther south smaller. So this means that the winds in the jet stream, which are driven by that temperature difference, are actually getting weaker. And this is something that we can measure.

We also know that by observing weather maps of the jet stream over the years, we know that when the jet stream is weak, it tends to take bigger swings to the north and bigger dips to the south. So think about what we’ve been experiencing in North America and the United States for the last few weeks where we’ve had a big northward swing over the West Coast and a big southward dip over the East.

This is the reason why we’re seeing this big difference in weather conditions over the West, which has been high and dry up until just a couple days ago, and California’s been dealing with an ongoing drought. And at the same time, a big southward dip in the jet stream in the East has allowed the cold Arctic air to plunge very far south into Florida and, as you described, snow in Tallahassee and conditions like that that are very unusual.

This big waviness, this huge wave in the West northward and big southward dip in the East has been what’s caused these unusual weather patterns that we’ve seen in the last few weeks. And we think that this rapid warming in the Arctic is leading to this kind of a very wavy pattern in the jet stream to happen more often.

GREGORY WILPERT: Then can we say that this type of more extreme cold weather may be the new normal due to climate change?

J. FRANCIS: Well, see, the problem is that these waves in the jet stream don’t always form in the same place. If we look back to 2012, for example, we saw the exact opposite kind of winter, where instead of there being a big northward swing in the West with warm, dry conditions there, in fact, they had very wet and cool conditions, whereas in the East, we set all kinds of high temperature records. So it really depends on where these waves set up across the continent.

But what we think is going to be the new normal is these big waves, so big northward swings, big southward dips. And when those waves are very large, they tend to move much more slowly from west to east, which means that whatever weather you’ve got, you’re going to be stuck with for longer. So really, the new normal, we think, because of the rapid Arctic warming, is more persistent weather conditions. Whether it’s hot, cold, dry, or wet, we think those probably going to last longer.

GREGORY WILPERT: Some, such as President Trump and, infamously, Senator Bob Inhofe with his “snowball chance in hell” stunt on the Senate floor, they say that this kind of extreme snowfall and weather disproves the idea of climate change. What is your reaction to such comments? Or to put it another way, what’s the relationship between climate and the weather?

J. FRANCIS: Right. A statement like that is what I would call myopic because it really only relates to the weather that they’re experiencing in their particular location, which happens to be cold in the East right now and back when Senator Inhofe made his famous snowball throw into the middle of the Senate floor. If you actually look around the world, the East has been one of the very few places on the globe that has been colder than normal. Almost everywhere else on the globe has been warmer than normal. So to make a statement like that is just plain silly.

And to just describe the difference between weather and climate, weather is sort of the fluctuations that we experience from day to day, whereas climate is the average overall of those weather conditions that you typically experience. So weather is what you get, and climate is what kind of you expect to have, what kinds of temperatures do you expect to have in January typically, but of course it fluctuates a lot day to day because of those individual weather systems that come along.

GREGORY WILPERT: To go back to your study, were there any other major findings that will affect our weather in the long term? And have other scientists found similar findings in terms of warming Arctic’s effect on weather patterns elsewhere?

J. FRANCIS: Yes. In fact, there are many issues that relate to the rapid Arctic warming, and probably one of the most certain ones that we know is happening, is going to affect literally billions of people is the fact that, because the Arctic is warming so fast, the ice not only on the ocean, which we call sea ice, is disappearing, that I mentioned earlier, but also the ice that exists on land. So these would be glaciers, the ice cap on top of Greenland, which is a couple miles thick in places. It’s a very, very thick ice cap. Those are all melting as well, and they’re contributing to the sea level rise that we’re experiencing around the world. So there’s a very clear connection between the warming Arctic and the melting land ice and sea level rise around the world. That accounts for about half of the sea level rise that we’ve already measured.

Those are the main ways that we’re seeing the Arctic affect weather patterns and people’s lives, but beyond that it’s also affecting the ecosystem. So we’re seeing, for example, bird migrations changing. There are many birds that migrate up to the Arctic in the summertime, and what’s happening is that because the Arctic is warming to fast that insects are hatching earlier there. The birds that fly up there are really taking their timing from the length of the day. So what happens is they get up there, and they find that the caterpillars that they went up there to eat had already hatched and already turned into butterflies or whatever, and so their food is already gone. Similar things are happening in the ocean. We’re seeing new species of fish never seen up in Arctic waters being caught up there. So there’s a while disruption going on to the ecosystem in the high latitudes as well.

GREGORY WILPERT: Do you think there is a possibility to reverse this trend of extremes and often dangerous weather patterns? And are we reaching a point of no return perhaps in terms of positive feedback loops?

J. FRANCIS: Well, the climate system is a very complicated thing. I have to say that I’m not optimistic that we are going to be able to reverse the course that we’re on. We’re headed towards at least several degrees of warming, globally speaking. The problem is that carbon dioxide, which is the main human-caused greenhouse gas that’s contributing to the global warming, lasts a really long time in the atmosphere, on the order of hundreds of years. So the carbon dioxide that we’ve already put in the atmosphere, we really haven’t seen the full response of the climate system to all that extra carbon dioxide yet.

So even if we were able to stop emitting greenhouse gases today, we would still see a lot more warming and a lot more impacts of that warming, including extreme weather, continuing into the future. So really, what we need to get a grip on is the fact that this is going to happen. We need to get a better understanding of what kinds of extreme weather we’re going to see in different parts of the world, in different seasons so that we can help decision makers in those local communities get ready for those changes. Things like drought and heatwaves and bad snowstorms and sea level rise and all these different kinds of effects that we know are going to happen but some of the details are still being worked out.

GREGORY WILPERT: Okay. Well, we’re going to have to leave it there for now. I was speaking to Dr. Jennifer Francis of Rutgers University’s Institute of Marine and Coastal Sciences. Thanks again for having joined us today, Dr. Francis.

J. FRANCIS: Any time. You’re welcome.

GREGORY WILPERT: And thank you for joining The Real News Network.