November 5 – Nice Ice, Baby!

Today’s factismal: Antarctica is losing ice at record levels. Antarctica is also gaining ice at record levels.

If there is one thing that everyone is willing to agree on, it is that climate is complex. (If there is another, it is that the media inevitably gets science wrong.) On a globe with as much topography and as large an ocean as ours has, it is entirely possible to have droughts, floods, record high temperatures, and record low temperatures all at the same time. As an example of the complexity our climate creates, let’s consider Antarctica.

Though Antarctica is covered with ice, it is really a desert (My camera)

Though Antarctica is covered with ice, it is really a desert
(My camera)

Located on top of the world at the South Pole (the Australians made me say that), Antarctica is about twice as large as Australia, making it the second smallest continent. Antarctica is unique in that it is circled by a current that helps shield it from some of the vagaries of weather in the rest of the globe. The Antarctic Circumpolar Current also blocks off moisture and helps keep Antarctica a dry, cold desert. But that is changing as the climate changes.

This is is the accumulation of eons worth of snowfall (My camera)

This is is the accumulation of eons worth of snowfall
(My camera)

About 30 years ago, several groups of climatologists pointed out that warmer air could carry more moisture. Now this may seem obvious, but the implications aren’t. The climatologists then pointed out that having more moisture in the air would lead to more precipitation especially in areas where the land rose up quickly. That’s because when the land rises up, it forces the moisture-laden warm air to go up as well. And as the moisture-laden warm air goes up, it cools thanks to adiabatic expansion (the same thing that makes a spray can feel cool in use). And once the moisture-laden warm air turns into moisture-laden cool air, the moisture would come out as precipitation. That’s what happens on the Cascade Mountains, which is why Seattle is lush and green where Spokane is dry and brown. So on the parts of Antarctica where the land rises up quickly from the sea, they expected to see more precipitation, which would lead to more snow which would lead to increasing ice levels.

Ice on the west side of Antarctica, where it is being lost in record amounts (My camera)

Ice on the west side of Antarctica, where it is being lost in record amounts
(My camera)

But Antarctica isn’t the same everywhere. On the eastern side of the continent, things do indeed rise steeply up from the ocean. But on the Western side, there are a series of small islands that cast a wind shadow on the mainland, robbing it of ice. As a result, the ice packs on the eastern side of Antarctica are growing faster than ever before while the warmer waters are causing the ice on the western side to retreat faster than ever before. So Antarctica is both losing and gaining ice at record levels!

Snow capped mountains in Antarctica are more common than ever - but they may not last (My camera)

Snow capped mountains in Antarctica are more common than ever – but they may not last
(My camera)

Now the way we know this is thanks to NASA satellites that measure the ice cover on Antarctica. Those satellites don’t stop there; they also orbit over your home and measure the ice and snow cover when you get it. And that’s where you can help NASA improve their data! The S’COOL project (which makes a great school project!) is looking for folks to go outside and look at the clouds when a satellite passes overhead. All you have to do is enter your location on the website and then go outside and tell NASA how cloudy the area is. They’ll use that to help ground truth the satellites and we’ll all get better climate and weather data thanks to you. To learn more, slide on over to:
http://scool.larc.nasa.gov/groundtruth.html

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