By Seth Borenstein
The Seattle Times/Associated Press
WASHINGTON — The harmful effects of global warming on daily life already are evident, and hundreds of millions of people won’t have enough water within a couple of decades, top scientists will say next month at a meeting in Belgium.
At the same time, tens of millions of others will be flooded out of their homes each year as Earth reels from higher temperatures and sea levels, according to portions of a draft of an international scientific report obtained by The Associated Press.
Tropical diseases such as malaria will spread. By 2050, polar bears mostly will be found in zoos, their habitats gone. Fire ants and other pests will thrive.
For a time, food will be plentiful because of a longer growing season in northern regions. By 2080, though, hundreds of millions of people could face starvation, according to the report, still being revised.
The draft document by the authoritative Intergovernmental Panel on Climate Change, a U.N.-organized network of 2,000 scientists established in 1988 to give regular assessments of Earth’s environment, focuses on global warming’s effects and is the second in a series of four reports this year. Written and reviewed by more than 1,000 scientists from dozens of countries, it still must be edited by government officials.
But some scientists said the overall message is not likely to change when issued in early April. Their plan will be presented to President Bush and other world leaders at a summit in June.
The first report, released early last month, concluded that scientists are 90 percent certain that people are the cause of global warming, that its effects are being felt and that it will continue for centuries. The report also noted that atmospheric carbon-dioxide levels are at their highest in 650,000 years, average global temperatures have risen about 1.3 degrees since the industrial age began and sea level rose nearly 7 inches during the 20th century, with the rate of rise more than doubled in the past decade.
The latest report — considered by some scientists the “emotional heart” of climate-change research — focuses on how global warming alters the planet and its life.
“This is the story. This is the whole play. This is how it’s going to affect people. The science is one thing. This is how it affects me, you and the person next door,” University of Victoria climate scientist Andrew Weaver said.
The scientists offer a ray of hope. The report says many — not all — of the predicted effects can be prevented if within a generation the world slows its emissions of carbon dioxide and if the level of greenhouse gases sticking around in the atmosphere stabilizes. But the scientists note that what’s happening now isn’t encouraging.
“Changes in climate are now affecting physical and biological systems on every continent,” the report says, in marked contrast to a 2001 report by the same international group that said the effects of global warming were coming, but only with scattered regional effects.
“Things are happening and happening faster than we expected,” said Patricia Romero Lankao of the National Center for Atmospheric Research in Boulder, Colo., one of many co-authors of the new report.
The document says scientists are highly confident that many current problems — change in species’ habits and habitats, more-acidified oceans, loss of wetlands, bleaching of coral reefs, and increases in allergy-inducing pollen — can be blamed on global warming.
For example, the report says North America “has already experienced substantial ecosystem, social and cultural disruption from recent climate extremes,” such as hurricanes and wildfires.
But the present is nothing compared with the future.
Global warming soon will “affect everyone’s life … it’s the poor sectors that will be most affected,” Romero Lankao said.
And co-author Terry Root of Stanford University said: “We truly are standing at the edge of mass extinction” of species.
Looking at different impacts on ecosystems, industry and regions, the report sees the most positive benefits in forestry and some improved agriculture and transportation in polar regions. The biggest damage is likely to come in ocean and coastal ecosystems, water resources and coastal settlements.
The hardest-hit continents are likely to be Africa and Asia, with major harm also coming to small islands and some aspects of ecosystems near the poles. North America, Europe and Australia are predicted to suffer the least harm.
“In most parts of the world and most segments of populations, lifestyles are likely to change as a result of climate change,” the draft report said. “Net valuations of benefits vs. costs will vary, but they are more likely to be negative if climate change is substantial and rapid, rather than if it is moderate and gradual.”