Not Too Late (Yet)

Whatever the Bush administration hoped to accomplish by muzzling NASA scientist Jim Hansen, it backfired. Hansen has become increasingly outspoken in recent months, calmly and firmly stressing his position that the world is poised to cross a very dangerous threshold unless it quickly gets a handle on runaway greenhouse gas emissions.

In the latest issue of MIT's Technology Review, devoted to energy technologies and global warming, author Mark Bowen (Thin Ice) profiles Hansen (read: "The Messenger"), whom he suggests "may be the most respected climate scientist in the world." Reading about Hansen, not just here but in various other sources, it's clear that he is not, by nature, an alarmist; it's just that the facts in the particular case are alarming. Consider, for example, the following. Bowen writes:

Running future emissions scenarios on a GISS computer model, Hansen finds that if we remain on the path he calls "business as usual," temperatures will rise between two and three degrees this century, making Earth as warm as it was about three million years ago, when the seas were between 15 and 35 meters higher than they are today. There go many major cities and the dwellings of about half a billion people.

Evidence suggests that the seas could rise in a matter of decades or centuries; recent events in Greenland and Antarctica indicate that the process may already have begun. The last great ice sheet collapse, about 14,000 years ago, sent the seas up a total of 20 meters, at the rate of one meter every 20 years for 400 years. Just the first meter would obliterate New Orleans...

That sounds like ample cause for alarm, even despair, but Hansen remains hopeful. In an attempt to look beyond the problem to solutions, he assembled an "A-Team" comprised of NASA scientists and other experts. According to Bowen,

They found that efficiencies based on existing technologies could buy time for a few decades, after which we must employ new technologies to cut global carbon dioxide emissions by 60 to 80 percent.

The A-Team found that growing emissions from coal-burning power plants and transportation posed the greatest threats. "Efficiency of energy end-use in the near term is critical for the sake of avoiding new, long-lived CO2-producing infrastructure," Hansen notes. "Green" building codes, combined with energy-efficient lighting and appliances, would be sufficient to hold electrical needs -- and the number of power plants -- constant for many years. The team also developed an achievable plan for limiting vehicular emissions, a plan that starts by improving fuel efficiency with existing technologies. It is "technically possible to avoid the grim 'business-as-usual' climate change," said Hansen last December. "If an alternative scenario is practical, has multiple benefits, and makes good common sense, why are we not doing it?"