Ice in Antarctica's Weddell Sea: Scientists are finding new evidence of long-term warming at the bottom of the world. (Newscom)
It’s getting warmer in Antarctica
By Pete Spotts | 01.21.09
For years Antarctica has been AWOL when it comes to continent-wide evidence of warming temperatures. Serious warming appeared limited to the Antarctic Peninsula, a mountainous finger of land jutting north toward South America.
No longer, if results from a new study hold up.
The continent is still bitingly frigid and largely a desert. The average annual temperature for the interior is -58 degrees Fahrenheit. Along the coast, it ranges from 5 to 14 degrees F.
But over the past 50 years, the continent as a whole has warmed (or grown less cold, if you like) by an average of 0.2 degrees F. per decade, according to a team led by Eric Steig, a geochemist at the University of Washington in Seattle. The pace is comparable to the rate of warming the southern hemisphere as a whole has undergone during that time, the team notes.
Warming usually seen on the Antarctic Peninsula now appears to extend across all of West Antarctica. The team estimated that temperatures on the peninsula have risen by 0.2 degrees F. per decade. West Antarctica has warmed at a rate of 0.3 degrees F. per decade. And East Antarctica has warmed at a 0.18 degrees F. per decade pace.
The team is a reluctant to unequivocally point a finger at human-triggered global warming just yet. A 50-year record is too short to allow researchers to sort out the relative contribution of human and natural influences to the trends they see at the bottom of the world.
Still, the results “are consistent with the general warming we get from greenhouse gases,” says Drew Shindell, a climate-modeler at NASA’s Goddard Institute for Space Studies in New York. Dr. Shindell is a member of the research team.
An understatement?
Indeed, the results may understate warming in some areas, suggests Gareth Marshall, a climatologist with the British Antarctic Survey. In an email exchange, he notes that the rate of warming as measured by stations on the Antarctic Peninsula have been somewhat higher than the rate Steig and his colleagues derived.
Still, he offers, the new results illustrate “that over the past 50 years overall, Antarctica has warmed at a similar rate to the rest of the Southern Hemisphere. This suggests that Antarctica, like the six other continents, is being affected by anthropogenic climate change.”
Portions of the new results appear to enjoy the beginnings of independent confirmation. A team of scientists from Swansea University and the British Antarctic Survey have found that temperatures at one location in West Antarctica have risen by 0.17 degrees C per decade since 1930. That’s virtually identical to the rate Steig’s team found for West Antarctica as well.
The British results are estimates based on temperature measurements the team made at various depths in a bore hole they drilled into the Rutford Ice Stream in West Antarctica. The hole is 1,000 feet deep. The results have been accepted for publication in the journal Geophysical Review Letters.
But one bore hole isn’t representative of a region, as the researchers readily acknowledge. They call on colleagues to make similar measurements to better pin down the rates and geographic reach of warming in West Antarctica.
Still, the two efforts “complement each other in a very nice way,” notes Brian Barrett, the lead author on the Geophysical Review Letters paper.
How they gathered their numbers
Steig and his colleagues had more data to work with. But they faced a problem. Of the 42 stations with records dating as far back as 1957 (the International Geophysical Year), only two sit within the continent’s interior. The rest dot the continent’s coast. So the team also tapped data from 65 temporary stations that scientists set up periodically for a few years as they conducted research away from long-established sites.
But that’s still sparse for an entire continent. So the team tapped satellite data to look at the continent as a whole. Measurements from on high only reach back 25 years. So the team used a statistical approach it developed to turn data from ground and space into a 50-year reconstruction of temperature trends.
Like Dr. Barrett, Steig encourages colleagues to begin taking more bore-hole measurements as an independent test of the results.
Even if the warming rate the team claims for East Antarctica — higher and colder than the western part of the continent — turns out to be more iffy than results for other regions of the continent, the results for West Antarctica alone should be a wake-up call, researchers agree. This is the area where large ice shelves are breaking up and the region’s ice sheet is thought to be the most vulnerable to melting over the coming centuries if industrial greenhouse-gas emissions and deforestation remain unchecked.
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2. Tangito | 01.22.09
It’s maddening to see how capitalist, who recently shot themselves in the foot with irrational speculation schemes, have resisted efforts to stop global warming for one reason: Greed. Their kids won’t have clean air, water ways will be polluted, oceans will swell, forrest fires will burn unchecked, clean water will be a thing of the past even if you can get some.
For what? Big cars you can’t afford to drive, big homes you can’t afford to pay the utility bills to keep heated/cooled. Oink, Oink!
3. severo alfredo clavijo | 01.22.09
Mientras las grandes empresas contaminantes continuen cerrando sus industrias el el hemisferio norte e intalandolas en el hemisferio sur el calelentamiento global se desplazará hacia la antartida. No es culpa de las empresas solamente, los gobiernos corruptos se asocian a empresas corruptas aceptando dádivas, congresos que aprueban leyes contra el pago de unos euros o dolares. El valor de la poblacion(individuo) es muy bajo en toda la america hispana desde la epoca de la colonia, para el hemisferio norte aún somos individuos sin valor. Mis saludos severo. Dios los bendiga.
4. Drew | 01.22.09
“So the team used a statistical approach it developed to turn data from ground and space into a 50-year reconstruction of temperature trends.”
I knew that this wasn’t really going to based on good data. As usual, the “evidence” consists of computer modeling. Guess what? These computer models are wrong more often than right. Ever look at the computer models for hurricane forecasting? They all dart off in different directions when they try to forecast even a few days ahead, and those are taking into account far more data than these “climate models” ever evaluate. It turns out that “pre”-casting (the opposite of forecasting) is just as unreliable without actual data.
Tangito, you clearly believe very strongly that what you have been told by Mr. Gore and company is infallibly true and will come to pass, and therefore I harbor no illusions about my, or anybody else’s, ability to change your mind. Consider, however, that many skeptics of the misomynous “climate-change” are simply pragmatic realists who want to see and know that the money our government appropriates is being used wisely - and certainly not being used to combat a phantom menace that may very well prove to be a global hustle and shakedown.
5. Iceman | 01.22.09
Michael Mann perpetrated fraud with his infamous Hockey Stick Graph.
Nothing he says can be trusted. He is a fraud.
6. philko | 01.22.09
So all of you who are slamming the study have read it? Or are you taking a quick popularized summary of the results that has appeared in the CSM and using that to judge the validity of the researchers’ methods?
You’ve already decided that AGW is bunk and are simply cherry-picking snippets from a summary and using those to “prove” that the study is flawed.
I won’t claim that the study is well designed and I won’t claim that it’s not. I haven’t read the *actual* report and, because of this, I realize that criticizing or praising it would be foundationless.
Try a bit of humility, people…
7. Jeff Id | 01.22.09
This study used massively infilled data to create a reconstruction. Some of the scientists on the papers list are the ends justify the means type. The satellite record isn’t air measurement record but rather ice measurement, they eliminated a substantial portion of the sat record because it didn’t match some pre-conclusion with the assumption (not the knowledge) that it was cloud interference.
Also, the UAH and RSS satellites don’t quite reach the antarctic continent due to orbital inclination but they come close. The ring of real temperature measurements which circumscribes the antarctic shows cooling. I am curious how this ring cools on average yet somehow through statistical magic, the continent warmed.
This issue is nowhere near closed and the reported confidence intervals are unrealistically small. I don’t care if antarctica warmed, I do care if bad science is used to make the claim it did. Statistics cannot replace real data.
8. FadingFast | 01.22.09
Typical climate change “science”. If the model doesn’t fit the data, change the data.
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1. Paulski | 01.22.09
In real data measurement, you cannot mix sources with other sources. This is a corruption of data. Each instrument and time has an associated data error. Secondly, bore hole temperature and air temperature would measure a completely different temperature change. Sat data is not reliable to measure within 5 degrees F. So how does being off by 5 degrees help determine tenths of a degree change? It does not. The gradations of your yard stick are bogus. This is real shoddy work. In the real world, your customer would not pay for such results; however, for university work, this is hailed as excellent.