This blog is intended to go along with Population: An Introduction to Concepts and Issues, by John R. Weeks, published by Cengage Learning. The latest edition is the 12th (it came out in 2015), but this blog is meant to complement any edition of the book by showing the way in which demographic issues are regularly in the news.

If you are a user of my textbook and would like to suggest a blog post idea, please email me at: john.weeks@sdsu.edu

Sunday, November 14, 2010

Will the Sea Rise Up and Grab Us?

Yes. The evidence is irrefutable that water temperatures are rising, glaciers are melting, and the sea level is rising. The only question to which we don't have a definitive answer is how much the rise will be. One or two feet one way or the other can make a huge difference in the number of humans at risk. The New York Times recently published a lengthy review of current knowledge on the subject. 

To a majority of climate scientists, the question is not whether the earth’s land ice will melt in response to the greenhouse gases those people are generating, but whether it will happen too fast for society to adjust.
Recent research suggests that the volume of the ocean may have been stable for thousands of years as human civilization has developed. But it began to rise in the 19th century, around the same time that advanced countries began to burn large amounts of coal and oil.
The sea has risen about eight inches since then, on average. That sounds small, but on a gently sloping shoreline, such an increase is enough to cause substantial erosion unless people intervene. Governments have spent billions in recent decades pumping sand onto disappearing beaches and trying to stave off the loss of coastal wetlands.
Satellite evidence suggests that the rise of the sea accelerated late in the 20th century, so that the level is now increasing a little over an inch per decade, on average — about a foot per century. Increased melting of land ice appears to be a major factor. Another is that most of the extra heat being trapped by human greenhouse emissions is going not to warm the atmosphere but to warm the ocean, and as it warms, the water expands.
Because we lack good data to model these changes, there is a certain casino approach to planning for the future. If sea level rises only two feet by the year 2100, then the problems will be less severe--albeit still severe--than if it rises by five feet. "A developing consensus among climate scientists holds that the best estimate is a little over three feet." Thus far, there seems to be little in the way of planning for this change, but adjustments are going to have to be made and the sooner they occur, the fewer the negative consequences there will likely be, because the rise will affect many of the major cities of the world, not just lonely beaches.

2 comments:

  1. The way I see it, and the only thing I truly see important in this issue, is that the the sea level is rising and we are increasing the rate at which it happens. That is the issue here. Obviously, we are interested in the rate at which it happens, because faster translates to more damage and being more dangerous, but whether its a lot or a little, its going to cause us problems. Seeing as we understand that we are a huge contributor in the rate at which it happens, or possibly if it even happens at all, it doesn't make much sense to spend so much time trying to figure out if the rate of rising is slow enough that we can get away with what were doing. Rather, we should be concentrating on finding solutions and acting upon what we already know to be fact, because we know that course of action couldn't hurt us.

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  2. Have a small-to-no impact, because that couldn't hurt! Punto! Nada mas!

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