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What's Hidden Under Greenland's Ice?
Roland Piquepaille writes "Ice has covered Greenland for millions of years. So what's hidden under this ice cap? Mountains and valleys? Rivers and lakes? Of course, we might know it sooner than we would have liked if the ice covering Greenland continues to melt. But researchers from Ohio State University have decided that they wanted to know it next year and have developed a radar to reveal views of land beneath polar ice. Their first tests of this new radar, which helps them to catch 3-D images of the ground under the ice, took place in May 2006. The next images will be shot in April 2007. Here are some images of the new GISMO device and what it can do."
Now if only the article you quoted said what you said it said, we'd have nothing to worry about. Unfortunately for you, the abstract itself indicates that the growth is only in the "interior areas" over 1500m in altitude, the height of the remainder of the ice (below 1500m) has been going down 2cm/yr (+/- 0.9)
Try again, unless you want to argue over how big the interior is relative to the parts that are shrinking and whether or not the water melting off the edges is flowing back uphill to the "interior" to freeze there, or running off.
Your link mentions a thickness increase in the interior only; there's a decrease on the margins. NASA says:
Another study and that NASA report points to an overall decrease in ice.
Sorry, but this was predicted by the models.
What happens is that warming causes ice near the edges to melt. This dumps cold freshwater into the water nearby, disrupting warmer ocean currents. It also increases humidity. Due to the disrupted ocean currents, the prevailing winds go inland, taking the humid air with it. This gets dumped as snow in the middle, causing the central ice dome to increase. A similar effect occurs in Antartica, where the central ice dome is about 4ks thick.
As shown in the link you provided, _below_ 1500m, the average change was a shrinking of 2cm (+- 0.9cm). Yes, the overall effect was to increase the thickness of the ice dome, but the dome is definitely getting more pronounced.
What the models predict next, however, is that as the slope of the dome gets more steeper, it gets unstable. You then get large stress fractures occurring, and huge slabs - say, about the size of New York State - break off and slide down to the ocean. Fun stuff.
Also, there's ice and there's ice. Old ice is very dense - it's been compressed over thousands or even millions of years, and contains more water by volume than the newer ice being laid down above. The main contributor to this is that the new ice has a lot of gas dissolved into it, or caught in bubbles. What this means is you can melt a million cubic meters of old glacial ice to get a bit less than a million cubic meters of water. However, the same volume of water (a bit less than a million cubic meters) falls as about 3 million cubic meters of snow inland, which gets packed down to about 1.5 million cubic meters of new ice. So, yes, the _volume_ of ice over Greenland is increasing, but the quantity of water in that ice is decreasing.
Here's an paper from the same March 2006 issue of Science that describes the process.
"Software is too expensive to build cheaply"
You can read the paper here. It was published in Science on August 10, 2006. Abstract:
First up nobody disputes there has been increased snowfall in Greenland's interior, in fact it was predicted by climate models.
Second, there have been more comprehensive and more recent studies from the GRACE sattelites, seen in the citation record at the bottom of your link. Also note in the GRACE mission statement that NASA purposfully designed the sattelites to measure the "exchanges between ice sheets or glaciers and the oceans".
Third, Johanessen et al. came to the best conclusion using the data they had, they just didn't have all the data available today.
Fourth, both the paper by Johanssen in your link and the more recent paper based on GRACE data from Rignot and Kanagaratnam agree with the predictions of climate models that say the interior will build and the edges will melt.
Last of all, allthough the result of 54cm is "very simple", measuring a volume of ice the size of Greenland is not a simple task and the error bars in the studies reflect that difficulty. Johanessen is a genuine skeptic when it comes to the impact of AGW, however even he does not doubt it is happening, nor does he doubt our CO2 emmisions are to blame.
It's also an accepted scientific "fact" that Greenland and the Antartic peninsula are subject to a phenomena called "polar amplification" which has seen their regional average tempratures rise by 3 degrees, compared to the global average of 1 degree. Now tell me again about "global warming scare mongering" or are you just trolling for AC's?
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
Just a Guess.. but maybe there is.. uh... green land under Greenlands ice caps?
Heh. Actually, we've known for a few decades that most of the interior is below sea level. Greenland is a big, backwards "C", with a ring of mountains around the edges and lower land inside. But when the ice melts, the land will slowly start rising, as has happened in Scandinavia, and there might be some dry land there in a couple thousand years.
And you should look up the history of the name "Greenland". It's a good example of what can be done with a dishonest marketing campaign. The Vikings that fell for it and settled there ended up all dying some time later, leaving behind only a few interesting archaeological sites. The smarter ones settled further south, despite the name "Iceland", so their descendants are still alive today.
This study will be interesting because it will give us details of the terrain under the ice. What we have now is the general contours showing that Greenland is a large bowl.
Those who do study history are doomed to stand helplessly by while everyone else repeats it.
We know that Greenland was actually "greener" when the Vikings settled it. The climate was warmer overall across the globe. It was not until the little ice age that Greenland became more like we tend to think of it and that settlement you speak of was lost.
*sigh* Global warming is not quite that simple, and frankly you're either an idiot or a troll.
What global warming means is that there is more energy in the weather systems of the world. That energy gets expressed as more _extreme_ temperature. The snow storms in Denver at the moment are just as much a symptom of global warming as the heat waves in Europe were in summer.
The weather is a vast engine that pumps heat energy around the globe. Global warming will result in this engine becoming unstable. One aspect of that may well be a complete breakdown of the heat-transfer mechanisms in the North Atlantic - which, in turn, would see glaciers in New York before too long, while, at the same time, causing the icecaps in Greenland and Antarctica to melt.
Climatology is hard. So's being a sane person with a brain, and not a troll.
"Software is too expensive to build cheaply"