Climate change doesn’t affect all places equally, and while Greenland and West Antarctica’s glaciers have started slipping into the sea at an alarming rate, East Antarctica was actually gaining ice. But now that could be changing, as a Nature Geoscience study done with data from NASA’s gravity-measuring satellites called GRACE suggests that the area could now be losing mass.
East Antarctica is far too cold, even in summer, for any appreciable melting to happen. And since a warmer world means more precipitation, any extra snow that falls on East Antarctica stays there indefinitely. But, starting in 2006, GRACE began to detect lower gravity over East Antarctica, suggesting that the ice sheet was getting less massive [TIME].
The scientists note that there is a huge uncertainty in their numbers: GRACE data suggests a 57 billion-ton-per-year loss, plus or minus 52 billion tons. (The reason is that the bedrock beneath Antarctica could be bouncing back slightly with less ice to weigh it down, which would cross up GRACE’s readings.) Some researchers are not convinced that the continent is losing mass, since the margins for error in the team’s analysis range between 5 and 109 billion tonnes of ice loss per year [New Scientist].
While the amount of East Antarctica ice loss remains in doubt, you can’t miss the huge chunks of Antarctic ice that have floated up near New Zealand this week and posed dangers for shipping. This is only the second time in 78 years that large Antarctic icebergs have been sighted so far north. The previous occasion was in late 2006 when icebergs could be seen from the eastern coast of New Zealand’s South Island, even from the hills around Christchurch [CNN].
Related Content:
80beats: Fossils of Shrimp-Like Creatures Point to Warmer Antarctica in the Distant Past
80beats: Floods Beneath Antarctica’s Ice Sheet Create a Glacial Slip-and-Slide
80beats: Antarctica is Definitely Feeling the Heat from Global Warming
DISCOVER: Grace in Space looked at the Grace satellites in detail
80beats: From 300 Miles Up, [Grace] Satellites See Water Crisis in India’s Future
Image: flickr / giladr
November 27th, 2009 at 12:12 am
I don’t think you can read too much into the icebergs currently heading to New Zealand. At least not in relation to any current loss of East Antarctic ice. They’re pieces that broke off the Ross Sea ice shelf in 2000-01.
November 27th, 2009 at 1:50 am
Just out of curiosity, how are “East” and “West” Antarctica defined? Are they divided according to the hemispheres? I ask since from the middle of the continent, any direction would be “north”.
In any case, not good news.
November 27th, 2009 at 4:46 pm
GAC, yes, East and West Antarctica are defined roughly by hemispheres but more precisely, if you look at Antarctica and draw a line through the Ross Sea / McMurdo Sound area across to the Weddell Sea / Ronne Ice Shelf area, you’ll see the Transantarctic Mountains, making a fairly clear distinction between the two sides, geographically most distinct because the East Antarctic Ice Sheet is the largest single piece of ice in the world, by far, while the West Antarctic Ice Sheet is something very different, sitting on dry land but anchored well below sea level in many parts of this side of the continent. Cheers ~ Ted ~ Cheesemans’ Ecology Safaris.
November 27th, 2009 at 6:33 pm
It would be interesting to find out whether or not an increase in fogs are noted around these icebergs as they reach warmere water as with the case off the coast of newfoundland with arctic icebergs[over 200 days per year].It could be an indication of where we are heading with an accelleration of ice breaking away from antarctica and reaching an accelerated warming ocean.
November 30th, 2009 at 4:18 pm
Sorry, but I’m no longer accepting any ‘facts’ about global warming and melting ice!
Climate change is a continuous process on Earth
December 8th, 2009 at 12:32 pm
JOHN: Hahaha… you’re not accepting any ‘facts’?! That’s okay whether you are ‘accepting’ them or not they are happening! While you are correct, climate change is a continuous process on Earth, I think it’s naive to believe that we do not affect it to some degree. People continue to site data that shows that the human element is so miniscule in comparison to more natural phenomenon. While they may be correct that it is a small percentage in comparison, they are not seeing the bigger picture. Our influence could be the straw that broke the camels back and that is why it is important.
Besides even if our influences was so minute that it actually didn’t matter to any measureable degree wouldn’t it still be important to monitor what’s going on with our earth? I’d like to know if there were some major climatic changes coming whether they were caused by us, cows, clouds, the sun, or whatever…
December 8th, 2009 at 12:57 pm
What effect does a lightening of the Antarctic continent have on the balance of the Earth? Could it possibly lead to another axis shift, such as has happened in the geologic past?
December 8th, 2009 at 1:58 pm
To Chuck:
I’m not a scientist, but I don’t belive the melting ice would affect the earth’s axis. The mass (ice and water) is still there whether it’s in solid or liquid form. Maybe a scientist reading your comment can explain it correctly. As I understand it, the earth’s axis shifts very slowly over thousands of years, maybe hundreds of thousands.
December 8th, 2009 at 2:13 pm
To William:
Here’s a little bit of simple background. Ice is solid and stays in one place (mostly) which is wherever the original snow fell that became compressed into ice. Water, being liquid, is spread over the entire globe, meaning that it affects ocean levels. This alone will raise ocean levels a certain amount.
The kicker comes when you factor in the fact that the Earth is spinning. That means that the water tends to be drawn toward the equator more than to the poles. Water levels in a band closer to the equator will rise much much more than the actual amount of water would suggest. This has a dire effect on most human populations, which tend to be in a band on either side of the equator.
I have seen some articles that suggest the shifting of these megatons of mass might change the axis tilt of the earth – I do not recall if anyone has worked out a model of the possible effect – but I’ll bet someone has.
December 8th, 2009 at 4:31 pm
Addendum to the above: The great Greenland ice sheet is also melting, as are smaller sheets in the Himalayas and perhaps Canada and Iceland. Another result is tectonic activity as the underlying bedrock is relieved of the weight of ice, and this might possibly lead to vulcanism as magma presses upward to replace the rock.
December 8th, 2009 at 6:39 pm
Science has proven that there were 3 Ice Ages (and reversals [warm-ups]), in its 5 Billion year lifetime! This was BEFORE man and/or man as a dominant species! In 1938, there were 3 Billion people; the population doubled in 70 years, by 2008. The World’s population is increasing by over 62 Million every year! Let us now calculate 2 more 70-year increases. That would put the World population at over 24 Billion people, (with a commensurate amount of animals AND agricultural needs) There are many things we can do without, but 2 of them are …NOT … BREATHING & WATER!!
70 % of the Earth’s water, is locked-up (saved up for humanity’s use), in the Antarctica, as ice/snow! With the advent of renewable energy system, supplying a never-ending amount of electricity, man can do the following:
Desalinate the oceans’ water for our consumption! Pipe-line water from areas which have too much, to areas that have too little. Out west, in the U.S., agriculture is already suffering from an inadequate amount of water for agricultural needs.
Eons from now, assuming man does NOT blow the planet up, copious amounts of electricity can then synthesize water, as needed! If necessary, it can als0 remove CO2 from water and air, and encase it into a rock-like substance!
The consumption of oil & gas, with the residues thereof, which the non-understanding alarmists claim, is the root cause of the alleged climate-warming, will be eliminated from consideration, because 140 year from now, Oil supplies will practically be depleted!
Next: Coal may be treated to reduce CO2 generation and also negate particle elimination by “scrubbing” methods, powered by electricity! NOT too much later, coal, being a finite resource, will NO longer be available! The key point to be made here is: MAN CAN NOT CONTROL THE CLIMATE,…. MOTHER NATURE , does NOT pay attention to unknowing politicians, AND continues doing its appointed job admirably … for man’s benefit!
December 8th, 2009 at 7:02 pm
If I were to walk into a bank and say I want to buy a house for $57K, and the amount of money I have is somewhere between $5K and $109K because my accounting is so imprecise that this is the best estimate I can muster, would the bank in it’s right mind loan me the money? In the same context, can Discover maintain credibility when it irresponsibly announces this error-buried non-fact to the world as evidence that Antartica might be melting? This measurement is so extremely preliminary, with so little substantiative basis, that it should not go beyond the speculations of the researcher’s lips much less be published as anything even close to speculative fact. It just shows how politics and wishful thinking has completely subverted true science.
December 8th, 2009 at 10:33 pm
I would suggest we err on the side that man does have an effect on this beautiful planet. It would benefit all the inhabitants (both man and nature), create lasting beneficial jobs and even perhaps lead to a better life if we chose to reduce our global energy demands and cut pollution. It’s that simple.
December 8th, 2009 at 11:39 pm
Climatic variations have happened many times in past. It has a pattern spreading over millions of years. It is sheer conceit of humans to claim that they are responsible to this event. The greed of the rest is busy in making a fast buck on this concept.
December 9th, 2009 at 9:09 am
Response to Landon:
Please note that, when the margin of error is calculated, it does not cross zero. Assuming the margin of error is calculated correctly, Antarctica is losing mass.
Put another way: Antarctica is definitely losing 5 billion tons per year. It could be losing 109 billion tons per year. This is significant.
The only major ‘if’ associated with this is ‘if the margin of error is calculated correctly.’
December 9th, 2009 at 12:31 pm
Note to Peter:
Thanks for your response. First of all, measurements usually need an error of 20% or much less to be be considered statistically significant. The admitted amount of error here is 91%, much more significant than the measurement itself. Secondly, the GRACE mission has been in operation only since March 2002. Seven years is not nearly enough time to establish normalcy, much less trends, especially in geology where time is measured in hundreds and thousands of years. To associate this measurement with global warming is total wishful thinking.
Note to Brian:
It is not an error to suggest that man has an effect on this beautiful planet – we do. However, it is an error to suggest that we have an unqualified negative effect. We are part of the natural scheme as much as any other animal. Man’s byproducts are handled in the same beneficial way as an animal’s, broken down and recycled. Man has shown some excesses, especially with new slowly-degrading substances – and we are learning how to handle them. But carbon dioxide has been around forever, and is deeply embedded in earth’s ecology/handling systems. Earth has absorbed far larger natural atmospheric swings in the past than man could ever impose today. In fact, earth directly recycles carbon dioxide into lusher plant growth, which immediately creates more oxygen. This is an intrinsic system that man cannot alter, even if we clear the rain forest (which I don’t recommend). Earth will simply grow something else to re-process carbon dioxide, even if it’s just weeds. To err on the side that we need to disrupt this process is not only a gross misunderstanding and an economic doom-boggle, but it can negatively affect earth’s natural cycles itself. Anything that animals naturally produce is not a pollutant! Let’s focus on reducing real industrial pollutants that nature had not seen before man produced them, like we already are. Let’s not listen to the politicians who only see the opportunity for the largest power grab in history at our individual personal expense.
December 9th, 2009 at 7:34 pm
So the ice melts and we find the lost city of Atlantis. Sweet!
…or Aliens. Cool either way, I say.
December 10th, 2009 at 1:51 pm
It’s heartening to see that, in spite of our beloved Discover Magazine getting more political, to the left, i/e assuming that global warming is indisputable, Bush bashing writers, etc., many of you here are thinking and disputing the assumptions that are taken by the left leaning, character assassinating people that readily accept those :indisputable facts.”