Why is Greenland & Antarctic ice melting faster than the models predict?
"We reconstruct the mass balance of the Greenland Ice Sheet for the past 46 years by comparing glacier ice discharge into the ocean with interior accumulation of snowfall from regional atmospheric climate models over 260 drainage basins. The mass balance started to deviate from its natural range of variability in the 1980s. The mass loss has increased sixfold since the 1980s. Greenland has raised sea level by 13.7 mm since 1972, half during the last 8 years."
- Anonymous8 months ago
Because the basis for the models changed unpredictably. The models are correct for what they were intended - the fact that the ice loss is and will be huge. They were never intended to be precise predictions.
- SagebrushLv 78 months ago
Because those who predict obviously don't know what they are doing.
As to your statistics about the ocean rise, that is a joke. And even if it were so, you couldn't reasonably attribute it to Greenland and the Antartic because there is simply no way of measuring that accurately. If there is, they must have been keeping it a secret because this specific calculation has not been continuouly published since 1972.
And as to your ignorant statement, "melting faster than the models predict," is completely without any historical background or logic. Thirty years ago the 'saviors of the earth' predicted that the Maldives would be under water within 30 years. But those on your side of the issue have too short of memories to remember that and it suits your crooked agenda. To a Liberal, history began an hour ago and they will even attempt to alter that if it fits their crooked agenda.
Besides, PNAS, although it sounds official, it still is a biased activist organization. The flooding and destruction in states like Nebraska, South Dakota, and Iowa are partly due to their intervention.
- Anonymous8 months ago
You are a Leftist sock puppet troll. This is a troll question set up to give your other account a 'best answer'.
Glaciers have been retreating for 20,000 years (when Chicago was under a mile of ice). 1910 was one of the coldest years on record according to NASA, and glaciers were rapidly retreating all over the world.
There has been a large increase in Arctic sea ice thickness and volume over the past ten years. The exact opposite of what government fraudsters_ tell the press.
- JimZLv 78 months ago
Long story, short, it isn't. Warming and sea level rise are far lower than the shrill predictions from not long ago. Your memory is fixated only on things that confirm your belief. That is the truth. Everything else is just spin.
I was in Germany for two years before the wall came down. I remember talking with this German that escaped from East Germany. Although he was smart enough to escape, he still had his brain full of Soviet propaganda. Mostly I'm referring to his beliefs about military technology and he informed me of all sorts of drivel and I was unable to set him straight. The modern left in the western world has become dumbed down like that guy. He really believes what he was told in spite of evidence to the contrary. In my life, I have seen Reuters, NYTs, ABC, etc become like Pravda and now I'd probably trust a story from Pravda more. Now we have these creeps in charge of the internet. It is pretty pathetic really.
Here is the chart from the EPA which you have to realize is flawed but I linked to it for whatever it's worth. Where is this supposed accelerating increase. It is like a snail accelerating from one inch a decade to 1.01 inches per decade. I'm sure the snail is impressed with that sort of "acceleration" but normal people still see it as a snail's pace.
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- samLv 68 months ago
too conservative estimates, better data
- ElizabethLv 78 months ago
I'd just add a few points to some of the other answers here ...
Humans have no magic crystal ball we can look into to see the future. What we can do in some circumstances is take the available theories and run computational simulations and models to try and see what the outcome might be. These aren't perfect but they're the best we can do. And hopefully, as we learn more, we get better at doing it.
Even if models give us a ballpark figure, it's better than nothing in terms of planning. If lots of different groups have slightly different data, analyse that data differently, make slightly different assumptions and all these groups come out with different predictions that still is useful - if all the models agree that the volume of ice being lost will be more than X amount, then at least we can plan for probably at least Y amount of sea level rise.
The problem I have is that some seem to be demanding absolute certainty before we take any action, whether it be on sea level rise predictions, glacier volume loss prediction, temperature predictions, etc. This absolutism is not applied to anything else. We don't apply it to earthquakes, tornadoes, viral outbreaks, and so on, yet no one argues that even though the models may not be as accurate as everyone wants, they aren't useful or helpful. Yet on the issue of global warming, suddenly it becomes a unique case where action is only warranted if and when 100% certainty is achieved.
- CowboyLv 68 months ago
The first rule of modeling is that the model is always wrong - it's a theory subject to constant revision as we learn more. But the model is our best well-researched estimate of what's going on. Climate models are often limited depending on access to the supercomputers needed to run the calculations.
And there's this:
"But these ecosystems also store huge amounts of carbon in soil and permafrost (aka frozen, ancient soil), more than twice the carbon that is currently in the atmosphere. As these ecosystems heat up, this carbon becomes increasingly vulnerable to microbial decomposition and release to the atmosphere. That in turn exacerbates warming, creating a feedback loop where warming begets carbon loss begets warming etc."
Winning at Climate Change: an Arctic and Boreal Story
- vulcan_alexLv 78 months ago
Models are mostly inaccurate as their data is not that accurate. Models can only be accurate if they have accurate detailed information, climate and even this limited area has inaccurate information.
- FLv 68 months ago
Faster? I thought Al Gore told us ALL the polar ice would be gone by 2011.
- Anonymous8 months ago
The model is not pinpoint accurate, even though it is correct.