Skip to comments.Weather, not climate, caused the brief surface melt in Greenland last summer
Posted on 04/04/2013 11:40:11 AM PDT by Ernest_at_the_Beach
Readers may recall the breathless wailing over a brief period of surface melt detected by satellites last year. The way the media and alarmists who drive the media behaved, youd think that global warming had set the planet on fire. Maybe their beef was over the red color in the satellite image that accompanied the press release.
Turns out this wasnt unprecedented as it happened before in 1889. Researchers suggested at the time that this event happens about once every 150 years.
From the University of Wisconsin-Madison today, we have the reason for the event weather in the form of thin clouds and air masses.
No wonder the public is ignoring the alarmists more and more, when they make claims like they did, and it turns out to be simply Mother Nature conducting business as usual, it tends to turn people off. Seth Borenstein, Joe Romm, and weepy Bill McKibben take note.
Thin clouds drove Greenlands record-breaking 2012 ice melt
MADISON If the sheet of ice covering Greenland were to melt in its entirety tomorrow, global sea levels would rise by 24 feet. (but it wont so why mention it? A)
Three million cubic kilometers of ice wont wash into the ocean overnight, but researchers have been tracking increasing melt rates since at least 1979. Last summer, however, the melt was so large that similar events show up in ice core records only once every 150 years or so over the last four millennia.
In July 2012, a historically rare period of extended surface melting raised questions about the frequency and extent of such events, says Ralf Bennartz, professor of atmospheric and oceanic sciences and scientist at the University of WisconsinMadisons Space Science and Engineering Center. Of course, there is more than one cause for such widespread change. We focused our study on certain kinds of low-level clouds.
In a study to be published in the April 4 issue of the journal Nature, Bennartz and collaborators describe the moving parts that led to the melt, which was observed from the ICECAPS experiment funded by the National Science Foundation and run by UWMadison and several partners atop the Greenland ice sheet.
The July 2012 event was triggered by an influx of unusually warm air, but that was only one factor, says Dave Turner, physical scientist at the National Oceanic and Atmospheric Administrations National Severe Storms Laboratory. In our paper we show that low-level clouds were instrumental in pushing temperatures up above freezing.
Low-level clouds typically reflect solar energy back into space, and snow cover also tends to bounce energy from the sun back from the Earths surface.
Under particular temperature conditions, however, clouds can be both thin enough to allow solar energy to pass through to the surface and thick enough to trap some of that heat even if it is turned back by snow and ice on the ground.
While low, thin cloud cover is just one element within a complex interaction of wind speed, turbulence and humidity, the extra heat energy trapped close to the surface can push temperatures above freezing.
That is exactly what happened in July 2012 over large parts of the Greenland ice sheet, and similar conditions may help answer climate conundrums elsewhere.
We know that these thin, low-level clouds occur frequently, Bennartz says. Our results may help to explain some of the difficulties that current global climate models have in simulating the Arctic surface energy budget.
Current climate models tend to underestimate the occurrence of the clouds ICECAPS researchers found, limiting those models ability to predict cloud response to Arctic climate change and possible feedback like spiking rates of ice melt.
By using a combination of surface-based observations, remote sensing data, and surface energy-balance models, the study not only delineates the effect of clouds on ice melting, but also shows that this type of cloud is common over both Greenland and across the Arctic, according to Bennartz.
Above all, this study highlights the importance of continuous and detailed ground-based observations over the Greenland ice sheet and elsewhere, he says. Only such detailed observations will lead to a better understanding of the processes that drive Arctic climate.
NOAAs Earth System Research Laboratory and the Department of Energys Atmospheric Radiation Measurement program contributed to the work at NSFs Summit Station, supporting collaborating scientists Matt Shupe of the University of Colorado Boulder, ICECAPS principal investigator Von Walden of the University of Idaho, Konrad Steffen of the Swiss Federal Institute for Forest, Snow and Landscape Research, UWMadisons Nate Miller and Mark Kulie, and graduate students Claire Pettersen (UW-Madison) and Chris Cox (Idaho).
What is even more amazing is that they constantly touch on solar output, sunspots, and the impact it has on terrestrial weather, they then immediately turn around and fail to note the connection!
I always love the AGW alarmist articles that initially call an event unprecedented and that later mention the last time it happened.
Whoda thunk it? Weather vs. Climate? Is that where short term ‘weather’ patterns as they call it allow their funky models to ‘predict’ what kind of weather might be?
Why in the hell didn’t they come out beforehand and tell us? Why wait until now to come up with BS equivocations about “weather vs. climate” and try and fool us.
Seems to me that if they collected all these “weather prediction models” and concatenated them into some sort of bigger simulation, their bullshit “climate” conclusions could be proven by a reasonable correlation.
In truth, they can do neither. They can’t take their ‘weather’ models, nor even actual recorded DATA (that isn’t falsified by Michael Mann and NASA’s Hansen, or East Anglia’s Climate Research Unit) and produce a correlated outcome.
I just don’t remember Iceland like that as a kid.. In fact, I don’t have any reason too.. even tho I come from a part of the continent long ago formed and shaped by glacial ice sheets.. hugh ‘uns. shift happens too,, as in the earth’s axis ,, over extended time we wobble.. and fall. thank goodness for LifeAlert,, and obamacare. :-}
So the weather isn’t part of the climate?