Saying Goodbye to Glaciers’: The Impact of Glacier Retreat
About half of the glaciers in Switzerland are expected to disappear in the next 25 years, and about 70% of the ice volume in Canada and in the Canadian Rockies will likely be gone by 2100, says University of Colorado research scientist Twila Moon
D Lascaris: This is Dimitri Lascaris for The Real News. One of the biggest icebergs on record broke away from Antarctica last week, garnering attention from around the world. The iceberg consists of approximately 5,800 square kilometers, which is about the size of the state of Delaware. But concerns about ice sheet stability and melting ice are by no means confined to the Antarctic region. Scientists have been documenting glaciers melting all around the world, and have also documented significant and apparently increasing levels of ice melt on the Greenland ice sheet.
How concerned should we be that climate change is reshaping the world? Joining us from Big Sky, Montana to discuss this is Dr. Twila Moon, who is a research scientist at the national show and ice data center at the University of Colorado. She specializes in understanding current changes in Earth’s ice, including the Greenland and Antarctic ice sheets. She’s also the article of an article published in Science Magazine entitled, “Saying Goodbye to Glaciers.” Thanks very much for joining us again Dr. Moon.
T Moon: Hi, thanks for having me.
D Lascaris: So as you say in your article, glacier volume is shrinking worldwide. What are some of the major glaciers where there has been extreme melting in the world?
T Moon: Well, unfortunately it’s a signal that we can see from pole to pole. So, we have large ice loss now from the Greenland ice sheet, which is losing ice every year, adding to sea level rise. We’ve seen places in, for example, Canada, where we’ve had large ice loss, especially in western Canada, and we can expect that to continue over the next decades. But really, you can run all the way from the north down to the south pole, picking out points in the mid latitudes as well as in the Arctic and Antarctic where we’re losing ice.
D Lascaris: And which communities are being affected the most by glacier retreat, and what are the primary impacts on those communities?
T Moon: Yeah, the impacts are really wide-ranging. I know that you’ve talk on the program about sea level rise, which is of course something that’s affecting coasts around the globe, but we also have to remember that ice is essentially a way of storing water. So glaciers around the world also provide really important drinking water sources. For example, communities all throughout the Himalayas depend on glaciers for drinking water or agricultural water during the summer. And that’s also true, for example, in Patagonia. We also see that glaciers and the melt that comes from them during summer is an important part of many ecosystems, so there are plants and animals that also depend on that. And then, of course, people depend on those ecosystems.
D Lascaris: And based on current data, physical and computer models, is there a timeline for the disappearance of the world’s major glaciers, a timeline in which we can have a reasonable degree of confidence?
T Moon: Yeah, so that varies for different locations at different times, and we have a broad sense of it, but there’s certainly still uncertainties. There are some things that we’ve been able to say scientifically. For example, we think that probably about half of the glaciers in Switzerland and gonna disappear in the next 25 years. We expect to lose about 70%, so about 7 out of 10 of the ice volume in Canada and in the Canadian Rockies by 2100, so in just the next 80 years.
So some of those smaller glaciers are what we’re gonna lose first. There’s a lot of ice in Greenland and in Antarctica. In fact, if we lost both of them, we’d have 60 meters of sea level rise. We don’t expect that kind of scale of loss to happen for thousands, maybe tens of thousands of years, but just having one meter of sea level rise, which certainly seems possible by 2100 now, that is already gonna have a really large impact on economies and coastal communities.
D Lascaris: Let’s focus on the major ice sheets, starting with Antarctica. There have also been reports that some parts of Antarctica are seeing thickening of the ice. Is that the case, and is that consistent with the hypothesis of ice melt caused by climate change?
T Moon: Yeah. That is true that parts, especially of eastern Antarctica, appear to be thickening, and that is consistent. What’s happening is, we’re warming up the atmosphere, and a warmer atmosphere can hold more water. And so it is able to hold more water and produce more precipitation in those parts of Antarctica. Unfortunately, western Antarctica, which kind of swoops around and reaches up towards South America, is losing ice. So, on the total, it looks like now we’re losing ice from Antarctica, and that’s even just a decade or two decades ago, it looked like Antarctica was perhaps a bit more balanced.
D Lascaris: And in terms of Greenland, is the rate at which … You talked about the fact that it’s shrinking the ice sheet, is the rate at which it’s shrinking, at which ice is melting, accelerating or is it increasing, and have we seen, in particular, any notable worrying developments in the state of the ice sheet in Greenland so far this summer?
T Moon: Yeah. So overall, over the last 20 years, the pace of ice in Greenland has been accelerating. Greenland, of course, much of the melt there happens from the melt of the surface of the ice sheet, and that depends on the weather each year. And weather is variable, so weather is kind of year to year, and climate is over 10, 20, 30 years. So this summer has actually been a relatively cold summer in Greenland, and we’ve gotten more precipitation than usual. This is due to some certain atmospheric conditions, and that’s been good news in Greenland for not losing … We’re not setting any new records in melting Greenland this summer, which is always good news. But unfortunately, this doesn’t change this multi-year trend of increasing ice loss from the ice sheet.
D Lascaris: And lastly, returning again to the skeptics, what is often said by those who refuse to believe in the science of climate change, that there’s a natural cycle of cooling and heating up of the earth, and that these are the normal variations that we would see given the natural cycle. How do you respond to that?
T Moon: Yeah. I think in many of those cases, it’s really important to remember the different time scales we’re interested in. So there are cycles that are connected to [inaudible 00:06:57] example, for the sun, and how close or far the sun is from us, or how much the earth is tilting, or some of these different things. But those are tens of thousands of years, those different cycles. This is heating up of the planet that we are doing in just the space of less than 100 years. So the time scales of these natural changes are much, much longer, and unfortunately, we live in a time where changes just year to year really matter to our economies, our populations, and the changes that we’re producing now are happening much, much faster than these kind of natural changes that we have seen over the geologic record.
D Lascaris: Well this has been Dimitri Lascaris speaking to Dr. Twila Moon of the National Snow and Ice Center at the University of Colorado. Thank you very much for joining us today Dr. Moon.
T Moon: Yeah, thank you.
D Lascaris: And this is Dimitri Lascaris for The Real News.