Worldwatch just released its State of the World 2009: Into a Warming World, which finds:

The world will have to reduce emissions more drastically than has been widely predicted, essentially ending the emission of carbon dioxide by 2050 to avoid catastrophic disruption to the world’s climate.

At a kick-off event, Dr. Rajendra Pachauri, chairman of the Intergovernmental Panel on Climate Change, said

President-elect Obama’s goal of reducing emissions to 1990 levels by 2020 falls short of the response needed by world leaders to meet the challenge of reducing emissions to levels that will actually spare us the worst effects of climate change.

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Told ya! (see “The U.S. needs a tougher 2020 GHG emissions target.”)

Pachauri was the guy handpicked by Bush to replace the “alarmist” Bob Watson. But facts make scientists alarmists, not their politics, as I’ve said many times (see “Desperate times, desperate scientists“). At the end of 2007, Pachauri famously said:

If there’s no action before 2012, that’s too late. What we do in the next two to three years will determine our future. This is the defining moment.

The Worldwatch report certainly supports that assertion:

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A chapter by climate scientist W. L. Hare concludes that in order to avoid a catastrophic climate tipping point, global greenhouse gas emissions will need to peak before 2020 and drop 85 percent below 1990 levels by 2050, with further reductions beyond that date. Emissions of carbon dioxide would actually need to ‘go negative’-with more being absorbed than emitted-during the second half of this century. Hare’s research finds that even a warming of 2 degrees Celsius poses unacceptable risks to key natural and human systems, including significant loss of species, major reductions in food-production capacity in developing countries, severe water stress for hundreds of millions of people, and significant sea-level rise and coastal flooding.

That is the emissions reduction needed if one wants to have a shot at stabilizing at 400 ppm CO2-eq (or lower), which is a very justifiable, albeit immensely challenging, goal (see “What’s the magic number?“).

In the introduction, Pachauri writes:

The strongest message from State of the World 2009 is this: if the world does not take action early and in adequate measure, the impacts of climate change could prove extremely harmful and overwhelm our capacity to adapt. At the same time, the costs and feasibility of mitigation of GHG emissions are well within our reach and carry a wealth of substantial benefits for many sections of society. Hence, it is essential for the world to look beyond business as usual and stave off the crisis that faces us if we fail to act.

Hear! Hear!

This post was created for ClimateProgress.org, a project of the Center for American Progress Action Fund.