I humbly suggest that all global warming denialists and skeptics should see the Doc "Chasing Ice". Photogrqph James Blalog spent a number of years building remote, self timed and solar charged camera systems, and then set up dozens of camera positions on glaciers in Greenland, Iceland, Alaska and Montana. Even if you don't believe global warming and climate change is real, or even if you don't believe it is human caused, the effort of doing what he has done is amazing. The visual imagery he has created is stunning, regardless of your opinions. Taking an image per minute over the course of many years, creates a fast motion video of how glaciers move, retreat and work. Other images are equally stunning. His crew camped out in front of Greenland's largest glacier in hope of capturing a calving. After 3 weeks of waiting in a tent in the high arctic, they were rewarded with one of the most awe inspiring natural event ever witnessed! A calving event, which released an ice berg the size of the southern half of Manhatten broke off in ~1 hour, throwing shards of ice 600' tall into the air. The resulting footage is nearly unbelievable if you begin to undstqnd the scale of this event! I actually saw the resulting Berg , grounded on the north coast of Newfoundland in the fall of 2011. One cannot come away from the film without a huge among of respect for nature, the drive and amity of James and his crew,, and perhaps most importantly a gripping visual record of what we, human, are doing to the planet,, believe it or not. Chasing Ice Icarus
Most grounded ice outside of Antarctica is in decline. Antarctica appears to be holding on to a balance, which is darned good news. I must tell you though of recently seeing excerpts of an interview with Lonnie Thompson, one of my ice heroes. He said that the last time CO2 and temperatures were this high was 3 million years ago. Fair enough. Then he also said that at that time, sea level was 20 meters higher. That was when I started talking back to the TV set. "No, Lonnie, don't say it!" But he did say it and concluded that the implication was that, by the end of the 21st century, the same sea level could occur. "No, Lonnie" The problem is with timing, the dynamics of the thing. We may have set into motion (by adding CO2) a situation that will eventually melt that much grounded ice. But not in 100 years. I don't know when the interview happened, so the possibility exists that this is where Al Gore got the ill-considered (and much maligned) idea for 20 meters in "the movie". Or 20 feet or whatever it was. Maybe we could make more sensible progress if there were a way to 'unspeak' some of these sorts of statements. Among them I would also include statements about air-temperature hoaxing, as they have been dismissed by the Berkeley temperature analyses. But as such things cannot be unspoken, we shall have to find a way forward even with additional rocks in the road.
20 feet, 20 meters, 100 years or 1000 years really doesn't matter except in perception. The fact is,, significant sea level rise, and deflation of grounded ice is already cooked into the cake. The only real question is what can we do about it? (and we are not even talking about feed back loops from methane in permafrost, or in sea water. Another point in the film, although almost in passing was the pockets of black carbon, largely from diesel exhaust and wild fires, acreateing in the ice, giving a great place for algae to grow, all into a black goo, contributing (significantly IMHO) to the change in albedo, allowing ever faster melting. I have seen this myself in the sub arctic as spring nears. Pockets in the ice, and on the snow that are decidedly darker due to black dust on the snow or ice, rapidly drilling down as the sun hits. It becomes a small feed back loop by it self. The warming adds to melt water, which in turn erodes more ice, the dark spots hold heat longer after sundown' adding to the melt load. (and heat up earlier in the morning). Air temps don't even have to gt above freezing for these pockets to melt, and remain unfrozen at air temps below 0c. I am no student of ice, but I spend a fair bit of my time on it, and I am genuinely in awe of what it does, and how it works. In the net, we know so little about the dynamics of ice that predictions as to how fast grounded ice will disappear are, it would seem to me, to be largely guess work. Icarus
Antarctica recently made the record high for ice. You wouldnt know it because the media isnt much interested. They only report record lows in the Arctic.
Antarctic ice is a matter of study, the first may be the most recent published: TCD - Abstract - Antarctic ice-mass balance 2002 to 2011: regional re-analysis of GRACE satellite gravimetry measurements with improved estimate of glacial-isostatic adjustment is positive NASA (see panel b) is negative. NASA - NASA Finds Polar Ice Adding More To Rising Seas NIPCC selects four from the literature: Recent Mass Balance Estimates of the Antarctic Ice Sheet So, don't miss those. I believe that one could find several different estimates of net mass balance, and that among them 'holding its own' is a fair summary. Or perhaps a slightly optimistic one. If Mojo @4 is advising me to not get science from the media, then I agree 100%. But, I already don't, so no policy shift.
Just a coincidence I suppose, but in Science (journal) today appears this: A Reconciled Estimate of Ice-Sheet Mass Balance I extract a quote "Between 1992 and 2011, the ice sheets of Greenland, East Antarctica, West Antarctica, and the Antarctic Peninsula changed in mass by –142 ± 49, +14 ± 43, –65 ± 26, and –20 ± 14 gigatonnes year−1, respectively." The last 3 refer to Antarctica. Add them = -71 GT/yr. But attend to the ±uncertainties, and you get something like 'holding its own'. At least to optimists like me. The right way to combine such uncertainties (so I was taught) is the square root of the sum of squares. So, -71 ± 52 GT/yr. Better to get that from the authors though. If you want to be similarly up to date on global sea level, there are a couple of reviews in the June 2012 Environmental Research Letters. Like Mojo says, don't get your science from 'the media'!
A newly released study finds that ice sheets in Greenland and Antarctica are disappearing three times faster than they were two decades ago, the latest evidence supporting the existence of global warming. The study was published in the journal Science and is considered an extremely accurate portrayal of ice melts in these polar regions. According to the paper’s authors, the rapid polar ice melting has caused an increase in sea level that may become problematic to low coastal regions. Perhaps the most alarming data found by the researchers was in Greenland where the ice was melting an estimated five times the rate it was in the mid-1990s. Melt from Greenland accounted for a whopping two-thirds of the polar ice melt. Due to a slower melt rate, just one-third of the world’s melted ice came from Antarctica, despite being larger in size than Greenland. Study on rising sea levels likely confirms existence of global warming | Science Recorder
That link is a little misleading on the research, which confirmed what most researchers though, and put some hard numbers out. Here is a link to the paper if you have a subscription A Reconciled Estimate of Ice-Sheet Mass Balance And a better summary if you don't Ice sheet melting accounts for 20% of sea level rise since 1992 - latimes.com
Doh, Didn't read the thread just the last response, and gave the same link to science and a slightly better summary from LA times for those that can't read the full paper.
The climate global warming deniers operate on religious faith not science so there is nothing that will change their views on the subject. They are dangerous obstructionist cranks in as much as they help the fossil fuel industries to fight the necessary changes to mitigate the problem.
This study is a bit out of date.Kind of takes the wind out of its sails when Antartica is at record highs and the Arctic recovered from its lows after a few days in Greenland or weeks for sea ice.
Why ice loss and sea level measurements via satellite and the new Shepherd et al paper are highly uncertain at the moment | Watts Up With That?
Oh here go again with Anthony Watts,, TV Weatherman! Here is what David Suziki says about Watts,, " David Suzuki recommends Skeptical Science for accurate science on the topic of climate change. "There are many credible sources of information, and they aren't blog sites run by weathermen like Anthony Watts".[21 Why don't we just take our science info from J. Fred Muggs? Icarus PS. To that end: "Although Glaciologists measure year-to-year changes in glacier activity, it is the long term changes which provide the basis for statements such as "Global Glacier Recession Continues". Some Skeptics confuse these issues by cherry picking individual glaciers or by ignoring long term trends. Diversions such as these do not address the most important question of what is the real state of glaciers globally? The answer is not only clear but it is definitive and based on the scientific literature. Globally glaciers are losing ice at an extensive rate (Figure 1). There are still situations in which glaciers gain or lose ice more than typical for one region or another but the long term trends are all the same, and about 90% of glaciers are shrinking worldwide (Figure 2). " Are glaciers growing or retreating?
I'll have to get the papers but I was thinking about the effect of rising sea levels on the Antarctic ice shelves. My understanding is some are held in place by islands. As the sea levels rise, it should 'float' the ice shelves and lead to more fractures and break ups. But it should also move the lubricating properties of sea water further ashore. Everything leading to more ice melt and flows off the land mass. Bob Wilson
