Archive for the ‘Ice Shelves’ Category

Ice & Us: There Is No Turning Back

Photo by NASA. Some rights reserved.

Photo by NASA. Some rights reserved.

The scientific community seems to talk about rising sea levels A LOT. This makes sense – as far as consequences of global warming go, it’s one of the easiest to explain, and one of the most potentially disastrous. We’ve looked at how a rise in sea level would effect us domestically and the results were not heartening. It’s pretty easy A-to-B math to see that if the sea level goes up, many coastal cities will be in critical danger of flooding and other natural disasters, and the entire ecology of the oceans will drastically change. And if that proof wasn’t in the pudding before, it sure is now.

Two new studies released this week confirm that the enormous West Antarctica Ice Sheet, the segment of the Western Antarctica continent that extends out into the Amundsen Sea, is losing mass at a rate that cannot be reversed. The ice sheet is estimated to weigh 25.4 million km3, however the accepted narrative in scientific communities for decades has been that it has been steadily and exponentially losing mass, to the point where snowfall is no longer replacing the amount of ice the sheet is losing. Between the years of 1996 and 2006, there was a 75% increase is the amount of ice mass lost, a statistic that seemingly should have set off alarm bells eight years ago. This week’s studies, then, should really just function as icing on a terrible, terrible cake, but judging by the reactions seen online, a lot of people were unaware that this was a problem.

The studies (one published in Science and one in Geophysical Research Letters) reach the same unsettling conclusion – the ice sheet is falling apart, and at this point the process cannot be reversed or delayed. The melting process will unsettle neighboring sections the larger continental ice sheet, and will result in a 10 + ft. rise in sea level. This will continue to happen slowly over the rest of the 21st century and speed up in coming centuries to the point of total global crisis. Coming on the heels of very pessimistic reports on climate change from the White House and NASA, it seems the gravity of the situation is finally starting to sink in on the Internet at large. I saw links to both of the aforementioned studies linked to dozens of times on many social networks by all sorts of people who normally wouldn’t be inclined to share this kind of stuff. The reality of climate change has, for many, finally gotten personal.

Revising the Antarctic Anomaly

Photo by NASA. Some rights reserved.

Photo by NASA. Some rights reserved.

Well, this is certainly intriguing! The big news in the environmental sphere this week seems to be the unexpected growth of Antarctic sea ice in 2012, an anomaly that NBC News calls a “global warming paradox.” Around here, we’re used to alarming news about the rapid decrease in Arctic sea ice. Heck, we’ve even seen reports that Arctic sea ice could be gone by the summer of 2016, if current trends continue. The Antarctic paradox, then, seems to be that though we’re nowhere near being out of hot water (pun intended) on the warming oceans front, the mass of Antarctic sea ice (where sea ice tends to be more scattered and mobile) seems to have grown to the massive size of 7.51 million square miles, the largest area of sea ice ever recorded in this region.

So… what’s the deal? According to National Geographic, the explanation has something to do with melting ice shelves. Where once the dominant theories on the subject pointed to heavier snowfall in the area brought on by warmer, moister air (which would in turn create heavier snowfalls that would reduce the saline levels in the top layers of the ocean, making them more stable), the scientists behind a new study are pointing to massive ice shelves that surround the continent melting down in higher temperatures, which creates a stream of fresh water flowing into the surface layer of the Southern Ocean and (as in the “more snow” theory) protecting the ice shelves from the warmer waters beneath.

However, this newest theory doesn’t seem to be definitive just yet. Other plausible explanations indict wind patterns as the culprit, while others say it could be a combination of all three factors (warmer air temperatures, wind factors, and melting ice shelves). I guess we’ll just wait and see?

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