2007年12月3日 星期一

In climate change, 'change' is the key word

Guest post from Jay Gulledge, a senior research fellow and staff scientist at the Pew Center on Global Climate Change.

With the release of the 4th assessment report of the Intergovernmental Panel on Climate Change (IPCC), we are going to see that the science of climate change has progressed rapidly over the past few years and that the scientific community will be willing to make much stronger statements about the causes and effects of climate change than ever before. The report will leave very little doubt about the reality of global warming and its causes, and I expect that it will become the foundation for moving forward on action to curb global warming.

In a recent interview on Good Morning America about the unusually balmy weather on the East Coast-it was 65 degrees and drizzling at 6am when I arrived ABC's studios in downtown Washington, DC-Diane Sawyer asked me whether global warming just means balmy winters and January blooms. I replied to the effect that it was nice to see some color in January, but that it represented a disruption to the normal biology of the plants and other organisms that interact with them, and that an ensuing freeze could literally nip them in the bud, leaving us with a drab, colorless spring. Although I stayed on topic, in retrospect, I don't think that was what Ms. Sawyer was getting at. I think she wanted to know what global warming means for people in their daily lives.

Scientists speak of averages, but people notice extremes. I recently heard Congressman Dennis Kucinich from Ohio ask, rhetorically, whether one needed to be a scientist to see that things are changing in our own backyards. In the years and decades to come, I think people everywhere will continue to notice changes in their own backyards because of global warming.

Change is the key word in climate change. For most people, this change will involve larger, more frequent extremes. For instance, in 2030 a Midwestern city will probably experience more rainfall, but it will likely come in fewer, larger events, with more frequent flooding. And between these events, there might be more frequent, longer, and hotter droughts. Residents of the city may come to expect 100+ degrees for many days running during extended droughts, when the soil is dry and no longer draws heat from the air. In summer, peak water and electricity demand will probably grow faster than city planners anticipated, requiring emergency infrastructure investments. With fewer hard freezes in winter, more pesticides will likely be needed to control mosquitoes and other pests. We will need to bolster emergency health care funds and disaster response systems to cope with these new extremes.

And, yes, the city residents will probably enjoy blooms in January too, but at what cost?

Jay Gulledge, Ph.D.
Senior Research Fellow/Staff Scientist
Pew Center on Global Climate Change

沒有留言: