Saturday, December 01, 2007

Antarctica Is Melting


The figure shows rates at which the ice-sheet mass was estimated to be changing based on radar-altimeter data (black), mass-budget calculations (red), and satellite gravity measurements (blue). Rectangles depict the time periods of observations (horizontal) and the upper and lower estimates of mass balance (vertical). Measurements by satellite techniques based on gravity indicate mass loss at a rate of 138 ± 73 billion tonnes per year during 2002–2005, mostly from the West Antarctica Ice Sheet. That is equivalent to a rise in global sea level of 0.4 ± 0.2 mm per year, or 10–30% of the global rate measured since the 1950s, and is in good agreement with recent massbudget estimates. However, two interpretations of satellite radar altimetry pointed to a much smaller loss of about 31 billion tonnes of ice per year or a net gain of about 27 billion tonnes per year. The difference between these estimates from totally independent techniques reflects the uncertainties in these difficult measurements; nevertheless, on balance, they indicate a recent shift to a net loss of Antarctic ice and suggest that losses may be accelerating. Similar conclusions result from studies of Antarctic Peninsula glaciers, indicating that they are melting much faster than previously predicted and are probably already contributing significantly to sea-level rise.

Contrary to what you might have heard.

h/t Michael Tobis.

7 comments:

Raging Ranter said...

The difference between these estimates from totally independent techniques reflects the uncertainties in these difficult measurements; nevertheless, on balance, they indicate a recent shift to a net loss of Antarctic ice and suggest that losses may be accelerating.

Now what is wrong with that sentence? "On balance"? If the science comes down to the best two out of three, why not just toss three coins in the air? How about just concluding that we have no farking clue yet, and urge more study? I know scientists want to be able to say they've made some kind of determination, but using a "best of three" approach to form an opinion, however preliminary, makes the author look rather amateurish. If a Master's student turned that into his board, they'd send him back to rewrite it.

heh said...

Oh, I see,

the north pole shrinking is "settled",

the south pole shrinking is not "settled".

Gee, I'm confused, I need a Liberal to tell me what is settled and what isn't.

It's all so......unsettling.

The Mound of Sound said...

Isn't it great when science gets critiqued based on the wording of news reports? It's the very same way that judges get smeared so often - by people who've never bothered to find out what went on beyond some inevitably incomplete ahd potentially misleading news story.

Anonymous said...

Well, I'll have to find the paper I read that showed the opposite.

Anonymous said...

http://www.lavoisier.com.au/papers/articles/landsea.html

Unrelated, but related. (That's a Dionism, btw.)

Anonymous said...

So again, what have all you good little eco-liberals been doing since 1995 to cut your CO2 emissions, seeing as how this is the WORST CRISIS TO EVER HIT THE PLANET!? (Even worse than GWB, I might say).

Moved into a tiny little apartment? Sold off all your internal combustion engines? Stopped flying? Only walk or bike? Only eat what is produced locally? Stopped buying products from across the globe? Grow your own vegetables?

Tell us; we're all dying to know how to emulate your behaviour.

Raging Ranter said...

Anon, it doesn't matter what they do. What matters is that they hold all the socially desirable opinions.

Take my own situation as an example. I drive very little, and own a fuel efficient vehicle that meets emission standards in California and Europe. I live in an apartment - a highrise no less. And I have yet to turn my heat on - it stays warm in here just from the surrounding apartments and the hallway forced air heating. I bus to work every day. All my light-bulbs are spiral thingies.

Yet I sometimes find myself being lectured by SUV-driving soccer moms and dads who live in 2500 sq. foot houses, about how we're just not doing enough to save the planet, and how my attitude is irresponsible and blah blah blah.

If I throw away a single sheet of paper, I get in shit - usually from some SUV-driving progressive whiner who cries all winter about being cold and demanding that the heat at work be turned up. Actions don't matter. Just think the correct thoughts, and you too can be an environmentalist.