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A picture from satellite data highlights the increase in summer melts in Greenland's ice sheet over the decade between 1992 and 2002  (Source: CIRES and CU Boulder)
Greenland's melt is increasing and continues a series of record setting years

Yesterday, DailyTech covered shocking allegations by an esteemed sea-level expert that the IPCC modified climate data and committed other violations in an attempt to falsely portray accelerating sea level rising.  If true, perhaps the IPCC should have learned to be more patient.

Greenland's melt is accelerating, according to a new study published as part of long-ongoing research at the Colorado University at Boulder on climate change.  In 2007, the summer melt record was surpassed by 10%.  CU Boulder notes that record breaking melts are nothing new to Greenland; the last 20 years have brought 6 record melts, with record melts in 1987, 1991, 1998, 2002, 2005 and 2007.

The base cause is clearly a surface air temperature rise.  Since 1991, extensive data shows that temperatures over Greenland's ice sheet increased approximately 7 degrees Fahrenheit on average.

The report by CU Boulder seemed objective and balanced in its observations.  It helpfully noted that the ice level actually had increased slightly at higher elevations due to increased snowfall over the past decade, however, it noted that this increase was not enough to offset the sharply escalating melting.

Professor Konrad Steffen, director of the Cooperative Institute for Research in Environmental Sciences which headed the study, gave a presentation on his team's research to the American Geophysical Union held in San Francisco from Dec. 10 to Dec. 14.  The paper that the presentation is based on, titled "Melt season duration and ice layer formation on the Greenland ice sheet," was published in the peer-reviewed Journal of Geophysics Research and is available here (PDF).

At the presentation, Professor Steffen put the melt in context saying, "The amount of ice lost by Greenland over the last year is the equivalent of two times all the ice in the Alps, or a layer of water more than one-half mile deep covering Washington, D.C."

Professor Steffen explained how his team used Defense Meteorology Satellite Program's Special Sensor Microwave Imager aboard several military and weather satellites to map the melt.  Professor Steffen supplemented this data with polled data transmitted via satellite from 22 stations on the Greenland ice sheet known as the Greenland Climate Network, which he and the University personally maintain.

Lubrication from the melting is one important factor that is speeding up the melt, as explained in Professor Steffen's research.  He stated, "The more lubrication there is under the ice, the faster that ice moves to the coast.  Those glaciers with floating ice 'tongues' also will increase in iceberg production."

If global warming critics or believers hope to use the melt as a quick smoking gun to prove sea level change, they shouldn't hold their breath.  Greenland is slowly and steadily contributing 0.5 mm of world sea level in melt water a year.  If all of Greenland's ice sheet melted, it is estimated that it would raise the global sea levels 21 feet, but for now it is just gradually raising them with time. 

However, deep tunnels in the ice known as moulins are speeding the rate at which water is evacuated into the sea.  With record melts, glacier lubrication, and these tunneling phenomena Professor Stephen expects the current yearly sea level contribution of 0.5 mm/yr to quickly rise.

He thinks that IPCC may have missed the boat on both ends -- overestimating sea level rise now, and underestimating future sea rise for the remainder of the century.  Professor Steffens has publicly stated that based on his understanding of Greenland's current melting process that sea level rise will significantly beat the estimates for 21st century sea level rise made by the IPCC Panel held in 2007.

Professor Steffens works for CIRES, which is a joint venture of CU Boulder and the National Oceanic and Atmospheric Administration (NOAA).  He and his team will continue to provide a voice of scientific reason in the global debate over whether melting is increasing or decreasing, with his team's diligent analysis of melting in Greenland.



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RE: Intellectual Neros
By TomZ on 12/13/2007 1:09:06 PM , Rating: 2
quote:
The only difference will be (20 - 30 years down the road): instead of saying "My scientists have data that show things ** really aren't that bad **...." or "This is just a cycle and is minimal when viewed in the context of a few generations".

30-35 years ago, early 1970's specifically, the same kinds of scientists were predicting a coming ice age and telling us to brace ourselves for that. Now all these years later, that is but a distant memory, and the right thing to do was to see how it played out before getting into a panic.

As Michael said above, there is a strong precedent for alarmism based on the current state of the art which is very poor ability to predict future weather and climate trends. Both in terms of pollution and global warming, which are really two separate things.

The right thing to do last time was to ignore it, and I don't see any real evidence this time to indicate that anything is really different. The evidence that global warming is happening quickly is weak, the evidence that it is largely human-induced is weaker, and the evidence that it will cause us large-scale problems is weakest of all.

Also remember, nobody I know of is here or elsewhere advocating a laissez-faire attitude towards pollution. Just CO2/AGW. Again, two different things.


RE: Intellectual Neros
By Rovemelt on 12/14/2007 1:34:39 PM , Rating: 2
Tom,

There is no denying that there were some predictions of a coming ice age in the 1970's. The general concept of global warming from greenhouse gas emissions was understood, however cooling from aerosols was also cooling the planet at the same time and it was believed that the forcings from aerosols would be greater than that from greenhouse gases. Forcings from aerosols turned out to be short lived. The popular press (Newsweek, Time) jumped on the coming ice age idea. The scientific community understood that climate science was in it's infancy and expressed that in the publications.

In a nutshell, what was said in the 70's regarding climate change and what's being published today are on two completely different scientific foundations. The sheer volume of climate data collected since the 70's alone should convince anyone of that.

From realclimate.org http://www.realclimate.org/index.php?p=94

quote:
Where does the myth come from? Naturally enough, there is a kernel of truth behind it all. Firstly, there was a trend of cooling from the 40's to the 70's (although that needs to be qualified, as hemispheric or global temperature datasets were only just beginning to be assembled then). But people were well aware that extrapolating such a short trend was a mistake (Mason, 1976) . Secondly, it was becoming clear that ice ages followed a regular pattern and that interglacials (such as we are now in) were much shorter that the full glacial periods in between. Somehow this seems to have morphed (perhaps more in the popular mind than elsewhere) into the idea that the next ice age was predicatable and imminent. Thirdly, there were concerns about the relative magnitudes of aerosol forcing (cooling) and CO2 forcing (warming), although this latter strand seems to have been short lived.

The state of the science at the time (say, the mid 1970's), based on reading the papers is, in summary: "…we do not have a good quantitative understanding of our climate machine and what determines its course. Without the fundamental understanding, it does not seem possible to predict climate…" (which is taken directly from NAS, 1975). In a bit more detail, people were aware of various forcing mechanisms - the ice age cycle; CO2 warming; aerosol cooling - but didn't know which would be dominant in the near future. By the end of the 1970's, though, it had become clear that CO2 warming would probably be dominant; that conclusion has subsequently strengthened.


Also,

http://www.wmconnolley.org.uk/sci/iceage/


RE: Intellectual Neros
By TomZ on 12/14/2007 5:46:21 PM , Rating: 2
I appreciate your thoughtful reply, however, there is a long history of poor correlation between climate model studies and actual reality. In the past, and continuing into the present, they have been very poor predictors of climate change, from what I understand. Models seem to be more detailed now, but I don't see how they are any more accurate.

For example, how many of these models correctly predicted the current leveling off of the previous rise in global temperatures?


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