The standard argument against taking action against global warming is that it might not really be so bad. After all, even the most sophisticated computer models cant say with any certainty whether the temperature will rise by a couple of degrees Fahrenheit over the next half-century or whether the increase will be five times that—or somewhere in between.
But a new report out of the British Met (for meteorological) office says that it doesnt have to get all that warm to be very bad indeed. There isnt any new science in the study, titled Avoiding Dangerous Climate Change: its a summary of research presented at a conference of the same name last year. But it does point out that the temperature need only rise about halfway to the worst-case scenario for such catastrophic events as the melting of the Greenland ice cap, or, worse yet, the West Antarctic ice sheet. The latter event could raise sea levels a whopping 5 meters, or about 16 ft., which could drown huge swaths of low-lying coastland and essentially wipe out countries like Bangladesh and the Maldives. Modest temperature increases could also shut off key ocean currents, like the Gulf Stream, plunging Europe into a mini-Ice Age.
All of these scenarios have been described before; what made this report so newsworthy was that the published version includes a foreword by none other than Tony Blair, who writes: "It is now plain that the emission of greenhouse gases's causing global warming at a rate that is unsustainable.
Luckily for Blair, he isnt working for NASA. Even as his comments were making headlines in England, James Hansen, a climate scientist working with the agencys Goddard Institute for Space Studies, told the New York Times that NASA brass are trying to muzzle his own outspoken comments about the imminent dangers of global warming. NASA officials say in response that Hansen is simply required, as are all employees, to clear public statements with the head office.