Mass Extinction Looms By 2050, Climate Study Finds

Global warming could force one-fourth of the globe's plant and animal species to the brink of extinction by 2050, according to a study published today in the journal Nature. Chris Thomas, University of Leeds conservation biology professor and lead author of Feeling the Heat:

Climate Change and Biodiversity Loss, said the earth's rising temperatures, in tandem with burgeoning agriculture and the proliferation of invasive species, would leave many plants and animals with vanishing habitats.

If all threatened species were able to relocate to more suitable climates, only 15 percent would face extinction by mid-century. If none could relocate, that number would soar to 37 percent, Thomas said, adding that the reality would doubtless lie between the two extremes.

"The midrange estimate is that 24 percent of plants and animals will be committed to extinction by 2050," Thomas said. "We're not talking about the occasional extinction - we're talking about 1.25 million species. It's a massive number."

Some species are equal to the task of migrating to new habitats, Thomas said, others less so. The silver-studded blue butterfly, for example, is a weak flier dependent on a food source found in clusters separated by large gaps, and it cannot make the journey between habitats (Guy Gugliotta, Washington Post, Jan. 8). In general, mountain species are better off since they can simply move uphill to cooler climes, whereas flatland species face the daunting task of making latitudinal adjustments (Paul Brown, London Guardian, Jan. 8).

The Washington Post reports that the study marks the first time scientists have analyzed the effects of climate change on a global scale. Whereas previous research has focused on smaller areas or species groups, this study combined the work of 19 scientists studying the decline of more than 1,100 species in five regions on four continents encompassing 20 percent of the earth's surface and a wide range of terrestrial zones (Gugliotta, Washington Post). It did not examine the oceans.

U.N. Environment Program Executive Director Klaus Toepfer said the report highlights the need to curb global warming through the cutbacks in greenhouse gas emissions outlined in the Kyoto Protocol. The global agreement has foundered on the unwillingness of the United States and Russia to impose restrictions on industry.

"This alarming report underlines again to the world the importance of bringing into force the Kyoto Protocol," Toepfer said (Alister Doyle, Reuters, Jan. 8).

Copyright, National Journal Group, 2004