Greenland Ice Sheet Melting 600 Percent Faster Than Predicted by Current Models
The climate is very capable of changing to another stable state unfavorable to the human species, and this is a real danger of our global experiment with unmitigated greenhouse gas emissions, says Arctic ice specialist David Barber
DIMITRI LASCARIS: This is Dimitri Lascaris for The Real News.
According to independent analyses by NASA, and the National Oceanic and Atmospheric Administration, Earth 2016 surface temperatures were the warmest since modern record keeping began in 1880. This makes 2016 the third year in a row to set a new record for global average surface temperatures. Heat records for the Arctic were also broken, and to a stunning degree. According to satellite data, the 2016 Arctic sea ice minimum extent, is effectively tied with 2007, for the second-lowest yearly minimum in the satellite records.
Climate scientists have been saying that, “What happens in the Arctic, doesn’t stay in the Arctic.” To help us understand why we should be very concerned about the dramatic shifts we are seeing in the far north, we are joined by Dr. David Barber. Dr. Barber is a specialist in sea ice and climate change, at the University of Manitoba, in Winnipeg. He holds a Canada Research Chair in Arctic System Science, and has over 30 years experience working in the Arctic. He leads a research group of more than 125 persons. He’s published over 140 papers in peer-reviewed literature, is a Fellow of the Royal Society of Canada, and is also an Officer of the Order of Canada. Dr. Barber, thank you for joining us today.
DAVID BARBER: Nice to be here, Dimitri.
DIMITRI LASCARIS: I’d like to begin by asking you to describe for us, in general terms, the effect that the planet’s warming is having now on Arctic sea ice.
DAVID BARBER: Well, a good way to think about it is the planet, as a whole, as it changes temperature, as it increases in temperature, it has a disproportionate effect as a function of latitude of the planet. We’ve increased by about 1 degree Celsius globally across the entire planet. But in the Arctic, we’ve increased, on average, two to three times that, relative to the rest of the planet.
And the reason for that is, the Arctic is an ocean covered by sea ice, and that sea ice is white. So, when you have solar insulation on the surface, it reflects that energy from the sun back to space when the white cover is there; when there is no white cover there, it’s a dark ocean and it absorbs that energy from the sun into the ocean. You then have to get rid of all that energy for sea ice to form in the fall, and that is one of the main reasons why we’re seeing an amplification of this global warming signal in the Arctic.
DIMITRI LASCARIS: Now, the polar bear has become a symbol internationally for the dwindling ice floe. But as we all know, the Arctic and the areas adjacent to the Arctic are quite sparsely populated. Why should those of us living in the more heavily populated parts of the planet be concerned about what’s happening in the Arctic?
DAVID BARBER: Well, I think there are many different reasons. One, is that people are very concerned about the Arctic itself, so if you really like polar bears, you’re very concerned about that issue the polar bears are having relative to their habitat. But if you’re more, sort of self-oriented, you’re thinking about your own personal situation, there’s also growing evidence that the changes that are going on in the Arctic are affecting other parts of the planet.
There are a number of different kinds of effects, and we call these things tele-connections. So, what happens on one part of the planet doesn’t just stay there, it affects other parts of the planet as well. This is not so surprising, because we all live on this single blue planet orbiting out there in space. And so we have to be concerned about our overall habitat as a human species, and the effects that climate change is having on that habitat.
DIMITRI LASCARIS: It’s my understanding that at one point in the fairly distant past, after the melting of massive levels of ice in North America, there was a dramatic cooling in Europe as a result of a change in the temperature of the flow of waters in the northern Atlantic.
Is that a scenario, that kind of scenario, one with respect to which there’s a significant risk of a recurrence? That something along the lines of, for example, the melting of the Greenland ice sheet could have a dramatic effect on the climate in Europe, or other parts of the Northern Hemisphere?
DAVID BARBER: Yeah. What you’re speaking of is what happens with meridional overturning in the North Atlantic. This is the way that deep water is formed on our planet’s oceans. And sea ice plays a very important role in that overall process of how ocean energy is circulated around the planet.
Now, historically, we’ve always felt that the amount of fresh water that you introduce to the North Atlantic had to be a very large amount of fresh water, for you to be able to slow down this overturning of this North Atlantic circulation. And of course, that fresh water historically has done that. And there is evidence from a paleoclimate record.
Paleoclimate records are when we go back and study different proxies of how the climate is changing. We can see, very dramatically, shifts, and very dramatic changes, based on the historical evidence in the Greenland ice sheet, for example. But also from other ice sheets around the planet, that there have been occurrences in the past where very significant, and relatively rapid changes have happened to our climate system. So, as climate scientists, we’re very concerned about that because it basically tells us that our planet is capable of shifting to another stable state relatively rapidly.
Now, whether this will happen or not, based on our changing climate in the Arctic, we really don’t know. And a lot of scientists are working on this around the planet, to try to figure out how sensitive the climate system is.
I think the take-home message for the public is that, we should not be experimenting with releasing very large amounts of greenhouse gases into the atmosphere more quickly than anything our planet has seen before in its historical past, because the climate is very capable of changing to another stable state and, of course, that’s not a good thing for us as a human species.
The displacement of people due to climate is a very big concern for us, because there are so many of us on the planet. And we don’t have a whole lot of, just sort of free room, to go and move to, once we have a climate problem in one part of the planet. So, it is a big sensitive issue, and something we have to pay attention to as humans inhabiting this particular planet.
DIMITRI LASCARIS: And thus far, we’ve been talking about the effect on ice of global warming in the northern hemisphere. What are we seeing in Antarctica currently? What are the current trends telling us?
DAVID BARBER: Well, it’s complicated, just like it is in the Arctic. But the general thing you see in the media is that the sea ice in the southern hemisphere is not shrinking as quickly as the sea ice in the northern hemisphere is. And that’s very true. But it’s also very expected by us who work on sea ice. And the reason for that is, that the southern hemisphere is a very large land mass that’s covered with a very large glacier situated right in the center of the southern pole, and then surrounding it you have this sea ice.
So, you have this very large cold source, that is losing mass quickly to the oceans, which is increasing the amount of fresh water that goes into the marine system in the Antarctic. And that causes sea ice to actually grow more efficiently.
In the northern hemisphere, we have an ocean surrounded by continents, which is a much different scenario. As we lose that sea ice in the northern hemisphere, we go back to this issue of a dark surface, versus a white surface, and that dark surface speeds up the removal of more sea ice in the northern hemisphere. So, that’s why we’re losing so much sea ice in the North Pole, relative to the South Pole.
Both of them are giving us very strong signals that this global scale record that we have, this global scale increase in temperature, is affecting both poles very substantially. And of course, the other big thing in the southern hemisphere is all this land ice. It’s the removal of that land ice into the ocean system, which then eventually melts, which leads to sea level rise. So, these are very important issues, both for the southern hemisphere, and the northern hemisphere.
DIMITRI LASCARIS: I’d like to conclude by talking a little bit about sea level rise. As we’ve discussed previously on The Real News, and as many of our viewers will know, in late 2015, the global community came together in Paris to enter into an international climate accord. Which established, as an aspirational goal, that we keep the global temperature increase to below 1.5 degrees Celsius, and set a somewhat harder cap of 2 degrees Celsius.
However, the emission reduction targets that have been submitted thus far, by the states that have acceded to that treaty, the scientific community is telling us, will result — if those emission reduction targets are satisfied but not exceeded — will result in global warming in excess of 3 degrees Celsius, perhaps closer to 4 degrees Celsius.
If the global community satisfies its current emission reduction targets, but does not exceed them, what kind of sea level rise do you think we will experience in this century?
DAVID BARBER: Well, first of all, I’m not a specialist in sea level rise, so I’m a little bit uncomfortable with giving you numbers. I’d rather talk more about the implications of this. What we’re seeing in the Arctic with the current situation, is that the cryosphere — so those portions of the earth’s system that are frozen, so lake ice, sea ice, glacial ice –- all of them are being affected. They’re all melting.
The Greenland ice sheet, we’re losing mass from it about 600% faster than what we expected. And of course, it’s the glacial ice masses that are really causing the sea level rise issue to be such an issue.
DIMITRI LASCARIS: … you said 600% more than what you expected. Do you mean, what you expected taking into account warming trends resulting from the introduction of CO2 into the atmosphere? Or, are you talking about historical melting, before the fossil fuels era?
DAVID BARBER: That’s… mmm. I think the quote that I’m thinking of, is 600% faster than what current models project. That’s based on greenhouse gas effects on the Greenland ice sheet. So, the situation is a serious one. Now, we also used to think that the Greenland ice sheet, and the ice sheets in the Antarctic, for instance, were a much slower process to lose mass to the ocean. We’re finding that they actually lose mass quite quickly, when you have ice shelves in particular, where these glacial features grow out over an ocean.
This is an issue for us in the northern hemisphere, when we have these fjords that are covered with ice shelves that come out overtop of the marine system. And they’re a big concern in the Antarctic, where you have large ones that come out overtop the southern ocean.
Now, when you think about the sea level rise that results from that, our models right now, almost all the models we use in climate science, are conservative, relative to what we’re seeing when we go out and do field studies. That’s a general statement that’s true across both hemispheres. If we were to start… if we were to not meet our goals that we have, we will be in serious trouble if sea level rise within this century. One of the big concerns I have, is getting away from the very dirty fossil fuels.
So, the idea of coal, and how we’re going to use coal historically across our planet, transitioning to more greenhouse gas-friendly types of hydrocarbons, natural gas in particular. So, I think it’s a big concern and something we have to get the politicians to realize, is that they’re trying to set targets for things that appear to be happening much faster than our models are predicting. So, the models are giving us even a bit of a sense of optimism, when they really shouldn’t be, because the observations are much more dramatic than the models predict.
DIMITRI LASCARIS: Right. Well, that happens to be precisely why we at The Real News are establishing a new climate change bureau, because we think it’s… all the scientists, like yourself, we’ve had on the program, and we’ve had many, have emphasized the need for our policymakers, our governments, to achieve a level of seriousness about the climate crisis that they haven’t demonstrated thus far, because otherwise we will be in serious trouble.
And for that reason, we thank you for joining us today, Dr. Barber, and I’m sure we’ll have the opportunity, or hope to have the opportunity, to speak to you again.
DAVID BARBER: Nice chatting with you. Have a good one.
DIMITRI LASCARIS: You, too. This is Dimitri Lascaris for The Real News.