Why is Arctic ice melting so fast?

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Right now, it's cold in the Arctic. Days are dark, and ice grows to cover the dark sea. Come summer, lengthening days and warming temperatures will reverse that process. This is the ebb and flow of the Arctic, a natural cycle.

However, over the past several decades we have seen summers melt more and more of the ice that forms during the cold winter months. As a result, more and more dark seawater is exposed to the light of day.

NASA researchers, using several instruments on three separate satellites, has been collecting data for 15 years to find out why the ice is melting, and to be able to predict trends in future ice formation and melting. They reported on this data at the 2014 American Geophysical Union annual meeting, saying that 15 years worth is the absolute minimum amount of information needed for them to begin making long-term predictions. Climate trends, as opposed to weather trends, are averaged over 30 years, so they are about halfway there at this point in time.

The project to observe the Arctic is part of NASA's Clouds and the Earths Radiant Energy Systems (CERES) mission. They measure the Earth's reflected solar radiation, emitted thermal infrared radiation, and all emitted and reflected radiation.

The results so far indicate that the Arctic is absorbing energy from the sun five percent faster now during the summer months than it was when they first began monitoring in 2000. This is important because the rest of the Earth is still absorbing energy at pretty much the same rate.

Put into energetic terms, this means each square meter of the Arctic Ocean is absorbing approximately 10 more watts of solar energy than everywhere else. Interestingly, this is not uniform, and is regionally specific. For instance, the Beaufort Sea has been measured at 50 watts per square meter.

All this extra energy has an impact on sea ice melt. The Beaufort Sea is one of the more dramatic ice melt examples. And, the rate of ice loss in September in the Arctic overall is 13 percent per decade. Let me spell that out... the Arctic is absorbing more energy, the air temperature is warming, and the rate of ice melting is being multiplied over ten times each decade.

So, why is this happening? It partially has to do with albedo, or reflectivity. Ice and snow reflect the sun's light and energy, while dark oceans absorb it. Less summer ice means that things are going to warm up faster, creating a feed-forward cycle that will potentially lead to even further warming and melting.

Walt Meier discussed differences in the ice itself that contribute to this process. He said that young ice melts more easily than old ice due to surface features and salinity. This results in much more rapid melting each year, which exposes more old, thicker ice to the suns rays. Each year more old ice is lost only to be replaced during the winter with easily melting young ice. The Arctic has lost 1.4 million square kilometers of ice over the past 15 years.

Young, thin ice makes the Arctic more vulnerable to further summer melting. Further Jennifer Kay, said that cloud cover is not related to the observed absorbed radiation.

 

Scientific message in a bottle

In 1959, geologist Paul Walker put this note into a bottle and left it buried inside a pile of rocks in a remote part of the Arctic. More than just a "GEOLOGY WUZ HERE" sort of message, though, the note requested that whoever found it measure the distance between the cairn that contained the bottle and a nearby glacier and send the measurement to him. The goal: To document whether the glacier was advancing or retreating.

A group of scientists discovered the message this summer and followed its instructions. What they found is probably unsurprising to anybody who has been paying attention to the state of Arctic ice over the last couple decades. In 1959, the cairn and the glacier were 168.3 feet apart. Today, there is 333 feet between them.

You can go wading in the lake at the North Pole

Last week, Dean told you about the lake at the North Pole, a pool of melted ice captured on camera by the North Pole Environmental Observatory webcams.

At Climate Central, Andrew Freedman provides some really fascinating context that illustrates the changing nature of, well, nature ... and draws a big, heavy underline on how difficult it can be to make assumptions about what is and what isn't an effect of climate change. Arctic sea ice is melting in concert with rising global average temperatures, but (contrary to the knee-jerk assumption I made about this story) the lake at the North Pole may or may not have anything to do with that. In fact, little pools have been forming at the North Pole in summer for as long as we've been paying attention. They don't actually represent the total melting of ice, but rather a layer of slushy water that forms on top of solidly frozen ice — usually, you could wade out through them and never get more than waist-deep.

What's more, the picture above wasn't taken at the North Pole. That's because the North Pole Elemental Observatory — which sits on mobile ice — has moved far from the actual North Pole since its launch. So, there probably is a lake (more of a pond, really) at the North Pole, but it might not be caused by climate change. While this lake, which isn't at the North Pole, could well be part of the melting sea ice that climate change does cause. But it also might not, because what happens as a result of climate change is always layered on top of stuff that just happens. In order to be able to tell the difference, you have to do a lot of scientific analysis — much more than you can get from one picture.

Read the rest

Oh nothing, just rare video of a polar bear mom nursing her cubs

Chris Thonis, writing to Boing Boing on behalf of explore.org, sends along this video of a mother polar bear in Churchill, Manitoba nursing her two cubs. Chris explains:

This is a behavior rarely caught on camera, and is the result of three live cams set up by explore.org, Polar Bears International, Parks Canada, and Frontiers North Adventure to capture the annual polar bear migration this year (the point being to get people to think more about how climate change is impacting the north, and inspire an annual event similar to Earth Day (or Groundhog Day).

Lazy harp seal has no job

Good luck getting this song out of your head.

Via Deep Sea News

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Watch an Icelandic glacier disintegrate

"The sound of running water is not something you used to hear on an ice cap." Arctic explorer Will Steger said this last weekend, during a presentation at the Science Museum of Minnesota. Steger was showing video clips from some of his travels, and he had to speak rather loudly. Otherwise, we couldn't have heard him over the sound of running water, flowing over, under, and through an ice cap.

Steger started traveling to the Arctic 18 years ago, and he's seen the region change dramatically over time. Today, he says, it's impossible to dogsled to the North Pole without bringing some kind of floatation device. You just can't rely any longer on the ice being solid all the way up.

But one of the most disturbing things Steger showed us was how global warming disintegrates glaciers. This isn't just about the melting that happens on top of the ice. It's really about what's happening below. Glaciers aren't a solid mass. Because they move, they're riddled with cracks and crevasses. When snow and ice on top of the glacier turns into water, there are plenty of ways for that water to seep down to the bottom of the glacier. Once there, the water acts as a lubricant. It makes it easier for the front of the glacier to break off and melt away into nothing.

You can watch that process happen in real time, as meltwater helps to break apart a glacier in a time-lapse video filmed between March 27, 2007 and March 4, 2012. About halfway though, the video reverses. As the glacier "rebuilds" itself, you really get the full impact of what's happened, and what is still happening, to our Arctic ice sheets.

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See more videos of melting ice filmed by the Extreme Ice Survey.

Learn more about the global outlook for ice and snow.

Learn more about how climate change is affecting the Arctic at the Will Steger Foundation website.

Eyewitness to climate change

Numbers can be powerful things, but they don't necessarily help the average person grasp what's actually going on in science. Instead, personal stories tend to make a bigger impact. And that's understandable. Things you can see—or things that someone can show you—are going to stick in your head a bit more than a barrage of data.

This is especially a problem, I think, with climate change. Some of the largest impact of climate change, so far, have happened in places far removed from the experiences of the people who create the most anthropogenic greenhouse gases. So it's often hard to take the idea "the Earth is getting warmer" and really grok what that actually means.

That's why people like Will Steger are important. Steger is an explorer and science communicator who has won the National Geographic Society's John Oliver La Gorce Medal—an award that's also been given to Amelia Earhart, Robert Peary, Roald Amundsen and Jacques Cousteau.

He does most of his work in the Arctic and Antarctic, places where he has clearly seen the results of climate change. In a video of a presentation at the University of Minnesota, Steger shows you his experiences—and what they mean. How has climate change altered the landscape of the poles? What does that mean for the future of the Earth? Steger does a good job of making the data feel like something real.

I wish I could figure out how to embed this, but you should go watch it, nonetheless. It's a long video, but worth the time.

Image: Ice berg melting., a Creative Commons Attribution Share-Alike (2.0) image from dkeats's photostream

Cutest video you'll see all day of penguins flying on a plane

[Video Link.] Yahoo's "Sideshow" blog has the story behind this video, and an accompanying photo gallery slideshow. On a recent Delta Flight, there were 300 or so human passengers and two foot-and-a-half tall penguins, Pete and Penny, who are 6 and 12 years old respectively. They were on their way to the New York premiere of "Frozen Planet," a new Discovery Channel documentary series narrated by Alec Baldwin. Like the narrator, the penguins fly first class. I hope they behaved better on the plane than he has been known to.

[photo: SeaWorld penguins Pete and Penny on display at the "Frozen Planet" premiere at Alice Tully Hall, Lincoln Center on March 8, 2012 in New York City. Astrid Stawiarz/Getty Images]

Watch starfish flee an icy finger of death

This clip from the BBC's Frozen Planet is one of the most amazing things you will ever see.

"Brinicle" is a clever portmanteau for an icy finger of death that forms naturally in the very cold seawater one finds around Earth's poles. A crust of sea ice can form on top of this water, and that's the first step to making a brinicle. Here's how polar oceanographer Mark Brandon explained the process in an article on the BBC website:

In winter, the air temperature above the sea ice can be below -20C, whereas the sea water is only about -1.9C. Heat flows from the warmer sea up to the very cold air, forming new ice from the bottom. The salt in this newly formed ice is concentrated and pushed into the brine channels. And because it is very cold and salty, it is denser than the water beneath.

The result is the brine sinks in a descending plume. But as this extremely cold brine leaves the sea ice, it freezes the relatively fresh seawater it comes in contact with. This forms a fragile tube of ice around the descending plume, which grows into what has been called a brinicle.

Check out that BBC website link for more information on how the Frozen Planet videographers captured this footage. That's also where you should go to watch the video when this YouTube version is inevitably taken down.

Thank you, Brittany. Truly freaking amazing.

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