Day 6

Greenland is melting: How winter heat waves are thawing Arctic ice sheets

In 2016, climate scientist Walt Meier produced a viral NASA video about the disappearing ice in the Arctic. Now, Greenland is reporting its warmest temperatures on record — and sea ice is melting at an astonishing rate.
Greenland's glaciers have been melting and retreating at an accelerated pace in recent years due to warmer temperatures. (David Goldman/The Associated Press)

The planet has seen a slow rise in temperatures over the years. But now, the warmest temperatures on-record are being felt across the Arctic, causing sea ice to disappear faster than normal.


So far this year, there have been 61 hours of above freezing temperatures in Greenland, compared to its previous record of 16 hours between January and the end of April in 2011.


Cape Morris Jesup, the world's northernmost weather station, confirmed this week it had recently recorded above freezing temperatures over a period of 24 hours.


Seeing these temperatures is particularly concerning for scientists like Walt Meier, who works at the National Snow and Ice Data Centre in Colorado. He's been tracking the ice for years now and even created a video for NASA documenting its disappearance in the Arctic.


Now thanks to this week's news out of Greenland, the video has gone viral more than a year after its release. Meier tells Day 6 guest host Rachel Giese about what all of this means, and why these changing temperatures are happening.


Walt Meier, senior research scientist at the National Snow and Ice Data Center. (Submitted by Walt Meier)


Rachel Giese: The video you produced more than a year ago showing satellite images of the changing ice around Greenland now has more than a million views. If you were to go out today and look from the northern coast of Greenland, what would you see?


On the surface, it would look pretty similar. But once you've got on the ice, once you looked at it in more detail, you're looking at a very changed environment. The ice is more broken up; thinner. It's more easily moved around by the winds and the currents. It might actually be a little bit more piled up along the coast because the winds tend to push it against the coast.


How quickly has this change happened?


We've seen the slow change over our entire satellite record [for] almost 40 years now. But where we've really started to see a rapid change and really dramatic change is in about the last 10 to 15 years where we've really seen a large decrease in the amount of the thicker and older ice that we see in the Arctic.



On top of that then, how alarming is the recent news from Cape Morris Jesup about the high temperatures?


It's a really dramatic indication of the change. We've had these kind of systems that bring in warm air in the past. But something this strong was extremely rare. And so, it's another indication that the Arctic is really fundamentally changing.


You've highlighted in the video and elsewhere that this is old ice that's being lost. What's the significance of old ice in terms of regulating temperature and climate?


Older ice is thicker ice. Ice that grows just from one summer to the spring the next year is only going to get to at most about two metres thick. Whereas ice that stays around for several years, continues to grow and gets upwards of three or four metres thick.


Basically, we've lost about half of the thickness. And with the thinner ice, it has less of an insulating effect on the ocean so more heat can get to the atmosphere. It's both an indication of the changing climate in the Arctic and it's also helping to drive those changes further.


Sea ice (TOP) meets land as seen from NASA's Operation IceBridge research aircraft along the Upper Baffin Bay coast above Greenland. (Mario Tama/Getty Images)


And does the loss of sea ice and these warmer temperatures add to the evidence then that climate change is the result of human activity?


I think it definitely does. One of the signatures and one of the things that was predicted early on is that the Arctic would warm faster than the rest of the globe. And, that's exactly what we're seeing. We're seeing Arctic temperatures rising two to three times faster than the global average and we're seeing about half of the ice cover remaining at the end of summer compared to when we started looking at the data 40 years ago.


This interview has been edited for length and clarity. To hear our full interview with Walt Meier, download our podcast or click 'Listen' above.