Fast ice

[unixronin]

The Jakobshavn glacier in Greenland drains 8% of the Greenland ice sheet.  In 1998, it approximately doubled the speed at which it is flowing into the ocean, therefore doubling the amount of fresh water it deposits into the North Atlantic.

In the last two years, the Helheim and Kangerdlugssuaq glaciers in eastern Greenland likewise doubled their speeds.  The two glaciers, 300km apart, drain 10% of Greenland's ice sheet between the two of them.  Researchers at the University of Wales in Swansea used satellite observations to determine that at their current speed of around 14km per year, the two glaciers are dumping 100 cubic kilmeters of ice into the ocean every year.

"Three outlet glaciers behaving in a similar way within a few years of each other and after a long period of stability implies both a common cause -- climate change -- and a high probability that other Greenland glaciers will respond likewise."

(Adrian Luckman, Geophysical Research Letters, vol 33, pp L03503)

Loss of the entire Greenland ice sheet would raise global sea levels by around six meters.  The good news is that current estimates indicate we'd have a couple of centuries to prepare for that.  The bad news is we'd be relying on governments to do it (which probably means the US, for one, would be totally unprepared).

Comments

[technoshaman.livejournal.com]

Mmmm-hmmm. So we're finally getting our heads around the idea that climate is changing. Finally getting enough data... hopefully enough to figure out that this is WAY bigger than any clean-air movement can fix.

Not, as I've long said, and Bob Roper before me, that it's polite to foul one's own nest.... but I think the important thing is that our energy doesn't have to be absolutely clean so much as it has to be, ultimately, absolutely sustainable. Nukes may be a stopgap, but they're not the end-all and be-all.

Which is why I'm glad I heard some snippet or other on NPR this morning about a car that runs on ethanol.... plant power is definitely the way to go.

[unixronin.livejournal.com]

Apparently, it's no longer necessarily true that ethanol fuel is energy-negative by the time production costs are figured in. It's also cleaner-burning than straight hydrocarbons ... then again, it also has a lower energy content. On the other hand, it doesn't detonate, so compression ratios can be pushed higher.

The gripping hand, though, is that it really doesn't make a lot of difference what we're burning, as long as we're burning it. We need to get away from internal (or external, for that matter) combustion as a power source, somehow. We need to start generating as much of our power as we can from wind, wave and solar sources, we need to generate locally as much as possible to minimize distribution losses (look up where electrical power goes in the US sometime ... distribution losses are KILLING us, in terms of overall efficiency), and we need to get ourselves a government that's not permanently lip-locked to Big Oil's tit so that we can make all this happen.