In a world whose demand for protein grows daily, the need to conserve stocks is plain. The remedies are not hard to grasp. Politicians, however, are supine. Few of them, especially in Europe, are ready to stand up to potent lobbies, except in small countries where fishing is so important economically that the threat of mass extinctions cannot be ignored.

Now bind the restless wave

Yet the mass extinction, however remote, that should be concentrating minds is that of mankind. It is not wise to dismiss it where CO2 emissions, the other great curse of the oceans, are concerned. In the long run, the seas are the great sink for nearly all carbon. They may be able to help avert some global war—ing¿for instance, by providing storage for CO2, by providing energy through wave or tidal power, or by somehow taking carbon out of the atmosphere faster than at present. They will, however, continue to change and be changed as long as man continues to put so much carbon into the atmosphere.

So far, the rising sea levels, dying corals and spreading algal blooms are only minor distractions for most people. A few more hurricanes like Katrina, a few dramatic floods in the coastal cities of the rich world, perhaps even the shutting down of a part of the world’s great conveyor belt of ocean currents, especially if it were the one that warms up western Europe: any of these would catch the attention of policymakers. The trouble is that by then it may be too late.

... contd.