Carbon emissions need to be cut dramatically by 2050 and “go negative” after that if we are to avoid catastrophic climate changes, says the Worldwatch Institute in its latest report.

The Washington D.C. based Worldwatch Institute, an independent research organization, has called for industrialized countries to slash their emissions by 90% by 2050, Reuters reports. These cuts, which could keep the global mean temperature from rising more than 2 degrees Celsius, are deeper than those called for by many climate experts and policymakers. President-elect Barack Obama, for instance, favours an 80% drop in U.S. carbon emissions by 2050.

The global mean temperature has already risen 0.8 degrees Celsius since 1850 and so the drastic cuts are needed now, co-author of the report William Hare told Reuters.

Hare said that global greenhouse gas emissions would need to hit their peak by 2020 and drop 85 percent below 1990 levels by 2050, and keep dropping after that. He said carbon dioxide emissions would have to “go negative,” with more being absorbed than emitted, in the second half of this century.

The burden of cutting greenhouse emissions should fall more heavily on rich countries than poor ones, Hare said, with industrialized nations reducing emissions by 90 percent by 2050, allowing developing nations to let their economies grow and develop new technologies that will ultimately reduce climate-warming gases.

Environmental advocates have hailed the report.

“It is a persuasive call to action,” Ian Lowe, president of the Australian Conservation Foundation, told the BBC. “Unless we take early concerted action, the impacts of climate change will overwhelm our capacity to adapt.”

Another co-author on the study, Robert Engelman, hopes that 2009 will be a decisive year for action, in part because government representatives from 170 countries are scheduled to meet in Copenhagen in December to craft a successor pact to the Kyoto Protocol.

Image: NASA