• live events
• bulletin boards
• caleb carr
mystery
|
At the lower end of this predicted warming range, the
temperature rise would take us back to the conditions that
existed between A.D. 950 and 1350, when the climate was
1°C (2°F) warmer than it is now. This time period
is regarded as one of the most benign weather regimes in
history. To find temperature swings at the upper end, you have
to go back 10,000 years, to when the earth was exiting the last
Ice Age. Temperatures during the Ice Age were 5°C
(10°F) cooler than they are now, and there was a series
of incidents during which global temperatures changed as much as
10°F in a matter of decades. If that were to happen now,
expanding oceans might flood coastlines and generate fiercer
storms. And as weather patterns changed, some places could get
wetter and some dryer, and the ranges of diseases could expand.
Civilization has seen--and endured--such changes in the past,
but they may come much more swiftly this time, making it harder
to withstand the jolts.
The main reason for the spread in the IPCC predictions is uncertainty about how much carbon dioxide will be added to the atmosphere by human activity, because how we will respond to the threat of climate warming is the greatest imponderable of all. We can probably develop technologies to deal with excess carbon--some scientists talk about removing it from smokestacks and stashing it underground--but the most direct way to control carbon dioxide in the atmosphere is not to put it there in the first place. This is the point of the 1997 Kyoto Protocol--signed by 84 nations but not ratified by the U.S. Senate--which would limit developed countries' carbon emissions from cars, power plants and other major users of fossil fuels. It makes no sense to overreact to the prospect of global warming, but it makes no sense to ignore it either. A prudent policy that stresses conservation and alternate energy sources seems to me to be wise insurance in an uncertain age. After all, our grandchildren will thank us for developing high-mileage cars, energy-efficient appliances and cheap solar energy, no matter how the future of global warming plays out. James Trefil is a George Mason University physics professor and author of 101 Things You Don't Know About Science and No One Else Does Either. |
SIDEBAR: ...And Then How Cold? Back to Question Page What Would a Green Future Look Like? What Will Happen to Alternative Medicine? Will Christopher Reeve Walk Again? Will There Be Any Wilderness Left? What New Things Are Going to Kill Me? Can We Make Garbage Disappear? What Will Be the Catch of the Day? |