Slight of Hand - 20 Foot Sea Level Rise
Posted by Max Dunn Fri, 27 Jun 2008 15:58:00 GMT
There are many ways to distort the truth. One of them is to suggest something as a possibility and then let uncritical minds repeat it as a fact. This is what is happening with Al Gore’s look at a 20 foot sea level rise.
One of the results of global warming is that it will cause sea levels to rise. This is due mainly to the thermal expansion of water and land ice melting. Of course how much it will rise is very important. If it is only a small amount, then there will be little noticeable affects but if it rises a large amount, it could cause massive flooding especially during storms.
In “An Inconvenient Truth” (AIT) Al Gore states that if Greenland’s ice dome or the West Antarctic ice shelf melted it would raise water levels worldwide by 18 to 20 feet. He also shows the devastation that would be caused if sea levels rose this much and states that tens of millions of people would be uprooted. (AIT Pages 109-117).
These figures have been widely repeated. For instance in Rising Powers, Shrinking Planet” (RPSP), by Michael Klare, he states “the catastrophic effects of climate change [will require] constructing dikes and seawalls … and relocating hundreds of millions of refugees.” (RPSP Page 59)
However, notice the slight of hand here. Al Gore never states that sea levels will go up by 20 feet or that Greenland or the Antarctic will melt. What he does say is “if” they melt, then sea levels would rise and devastation would occur.
But the key word here is “if” and neither the IPCC nor any credible expert in this area sees much likelihood of this actually happening anytime soon. In reality, the IPCC projects that sea levels will go up by 11 to 17 inches by 2100. (IPCC AR4 Page 323) This is a lot less than 20 feet!
Even a 2 foot sea level rise sounds bad until you look at sea levels historically. In fact, sea levels have been rising for a long time. Since the last glacial maximum about 20,000 years ago, the sea has risen about 400 feet as a result of major ice sheets melting. In the last 6,000 years seas have risen about 10 feet, and in the 20th century alone, the have risen 8 inches (Wikipedia: Sea Level Rise). So even without man-caused global warming, we shouldn’t be surprised that the sea level continues to rise.
Therefore, be careful when you hear a statement like this. Listen carefully to what is being said to determine if the speaker is saying this will actually happen, or if they are only suggesting it as a possibility. Also be sure to check their sources and other experts before taking a statement like this as fact.