2010-08-27 09:33:28BASIC rebuttal #117. Greenland has only lost a tiny fraction of its ice mass. REVISION 1
villabolo

villabolo@yahoo...
76.93.65.8

 Greenland's ice loss is accelerating and will add meters of sea level rise in the upcoming decades and centuries.

In 2002 NASA satellites detected a loss of 137 billion metric tonnes* of ice for that year. In the period from 2007-2009 there was a loss of 286 billion tonnes** of ice for that year alone. That was a doubling of the rate of ice loss in 7 years.

The most frightening statistic just mentioned is not the hundreds of billions of tonnes of ice. That does seem like a lot but not compared to the total amount of ice Greenland has. The really important number to keep in mind is the number two, as in doubling.

This means that the loss of ice in Greenland is starting out small at present but will greatly increase within the lifetime of today’s children.

Below, there are some illustrations provided to help visualize the amount of ice that is being lost. 

*   Tonnes is the spelling for a metric ton. A metric ton is 1,000 kilograms or 2,205 pounds.

 

** (Velicogna 2009). 

 


                                                             

Empire State Building compared to 1 gigatonne of ice                 Empire State Building versus rate of ice loss from Greenland in 2002 to 2003

 

 

 

 

Empire State Building versus rate of ice mass loss from Greenland over 2008 to 2009

 

 

 

2010-08-27 09:43:24Whoa, boy!
nealjking

nealjking@gmail...
91.33.114.71

I have never seen anywhere, and certainly not in John Cook's intermediate article, the claim that the rate of ice loss was going to increase exponentially, as you suggest with your powers-of-2 calculation. This is way over the top.

Please go back to JC's article and try to express the gist of that. Simplification does not mean exaggeration.

2010-08-27 13:09:10Comment
Robert Way

robert_way19@hotmail...
142.162.191.40
I think this rebuttal needs more focus as 3 different arguments are put forward. Another thing to consider is that mass losses from ice sheets are very hard to predict and assuming an exponential relationship is quite a stretch. Although you should see losses increase in the next few years as the Northwest sector keeps losing mass, I would not expect that you'll see a truly exponential relationship. I think its important to state something like "yeah if it continued doubling at this rate it could dissapear in X number of years BUT that is completely unrealistic. However it does go to show that making wide ranging statements like that it would take 10,000 years to melt are irrelevant."

It's a hard topic but just try to stay on course with JC's one.
2010-09-08 09:10:55
doug_bostrom

dbostrom@clearwire...
184.77.83.151

New information: 

http://www.sciencedaily.com/releases/2010/09/100906085152.htm

Refinement of GRACE results indicates Greenland, Antarctica ice loss may be less than previously believed. 

2010-09-10 06:30:41Rework.
villabolo

villabolo@yahoo...
76.93.65.8

I'm going the have to rewrite this one due the new information concerning GRACE. I will also have to drop the illustrations since they are no longer accurate. When I have the time, I will try to find exact figures for the ice loss. All I've found so far is a statement that says "...half the speed originally predicted.". Needless to say, that won't make a good citation.

VILLABOLO