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Old January 11, 2008, 08:46 AM
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shaad shaad is offline
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Join Date: February 5, 2004
Location: Bethesda, MD, USA
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A few issues are not covered in this otherwise well-written report. Keep in mind, though, that I am not a geologist or climate expert, just someone thinking about this issue.

First, there is an assumption in this article that sea levels will continue to rise at the same steady rate, 7mm/year, leading to a relative but easily manageable increase of 1 mm/year. However, there are a body of climatologists who expect the rate of sea level increase to accelerate as ice sheets begin to disintegrate in a rapid, non-linear fashion on West Antarctica, Greenland or both (there are multiple positive feedback effects besides just basic greenhouse warming that could come into play to increase this rate, e.g. reduction in the earth's albedo, i.e. reflectivity; increase in vegetation at higher altitudes; surfaces of ice sheets at lower, warmer altitudes, causing increased melting, etc.) and it would have been appropriate for the writer to consider these issues.

Second, the writer's expectation of a relative increase of 1 mm/year is based on silt (alluvial soil) continuing to be deposited at the same rate by our river system. However, he enters into no discussion whatsoever of how the rate of flow of our river system, and thus the rate of deposit of silt, will be affected by climate changes brought about by global warming (e.g. change in levels of precipitation), geological changes (e.g. amount of snow in the Himalyas) and geopolitical reality (e.g. barrages/dams and canals built by our neighbours that could choke off the flow of water and thus silt coming down our delta.)

Third, there is no discussion of the effect of salination brought about by rising sea water. Alluvial soil is fertile indeed, but that fertility will not help rice or other crops grow in salt water. Already, several farmers along the coast have shifted to cultivating marine shrimp instead. And our freshwater based mangrove forests in the Sundarbans are already at risk.

Finally, I am a scientist by inclination and training, not a pessimist. That means, among other things, that we prefer not to wait for a full-blown problem to actually land in our laps before scrambling to find a solution. We would much rather consider the potential problems and risks of any situation beforehand and begin to devise solutions before they become a full-blown crisis. If an accelerated rise in sea-levels does occur, I believe we Bangladeshis, as a people, will be able to meet the challenge. But make no mistake, the situation will be considerably different and more difficult than that which faced the Dutch. It will require planning, and one hopes that at least some people in our government are actually thinking about it, not dismissing it out of hand as the writer appears to do as an attempt to get foreign aid.
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