Is the sea level rising?

Saint Martin’s Island, on the coast of Bangladesh (picture Niaz Morshed)

The Spectator last week questioned the reports that sea levels around the world are rising.  (Read the article, by Nils-Axel Mörner, here.)  Higher sea levels are generally expected to be one of the consequences of global warming, so if sea levels do not rise (or, rather, do not rise in a pattern different to the one they have followed up until now – they rise and fall, and are never still) that casts doubt on whether global warming is really happening.

Publication of this article drew a furious reaction from critics, pointing to its scientific errors and highlighting its lack of credibility.  (For example, George Monbiot here.)    This website is not competent to judge on the arguments about sea levels as such: our focus is on the policy framework that would be needed to do something about it.  If countries are following policies that suit themselves but harm others, then we’re interested.

And we are interested here.  First, if George Monbiot is right, then the problems of climate change cannot be dealt with properly by existing political institutions.  (We explain why not here.)

But what if Nils-Axel Mörner is right, and sea levels are not rising?  When then?  Well, look at the reasons he advances:

In Bangladesh, for example, increased salinity in the rivers (which has affected drinking water) has in fact been caused by dams in the Ganges, which have decreased the outflow of fresh water.

OK, but where are those dams?  There are several within the Ganges river basin, for example Tehri Dam in Uttarakhand, Bansagar Dam in Madhya Pradesh, and Farakka Dam in West Bengal.  What Uttarakhand, Madhya Pradesh and West Bengal have in common is that they are states not in Bangladesh but in India.  (Read about this website’s interest in river basins here.)

So, if there is evidence that sea levels are not rising in Bangladesh – showing that countries have not been pursuing policies that are selfish environmentally – it is because of dam construction in India, a policy that is selfish environmentally.  Whichever way you look at it, self-consciously national environmental policies are part of the problem and not part of the solution.

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