State of the World 2009. Photo: Courtesy Worldwatch Institute

President-elect Obama wants to work toward reducing greenhouse-gas emissions by 80 percent by 2050, but a new study from a D.C. research group says even that rate won’t be enough to avoid potentially catastrophic disruptions to the world’s climate. The Worldwatch Institute, which sounds a little like a group with an underground lair in a James Bond film, released its 2009 State of the World report this week, claiming the world will have to reach near-zero emissions by mid-century if it wants to avoid the worst consequences of a changing climate.

As you might guess from the title “State of the World,” the annual report is ambitious in scope, synthesizing an impressive amount of climate and energy research and recruiting a variety of scientists and analysts to write chapters. It includes chapters on how to restructure energy systems, rural land use, and the “resiliency” of political and social networks as they strain under the effects of climate change. The institute says it included more contributors from developing nations than ever before, because those countries are likely to be the most affected, and least equipped to adapt, to climate change.

In an early chapter, climate scientist W.L. Hare tracks the increase in our planet’s average temperature since the start of the Industrial Revolution in the mid-18th century — 0.8 degrees Celsius (1.4 degrees Fahrenheit). He calculates that a further increase of even 2 degrees Celsius — an amount climatologists predict will be very difficult to avoid given the world’s continued reliance on fossil fuels — would trigger rising sea levels, coastal flooding, major disruption to food-growing in developing countries, and reductions in biodiversity.

Much of the rest of the report focuses on solutions. In one of the strongest chapters, on farming and land use, Sara Scherr and Sajal Sthapit explain that the Earth’s soil and vegetation hold some 2,000 billion tons of carbon, three times as much as the atmosphere holds. They sketch out five land-use techniques that would slow the damage of climate change: enriching soil carbon, creating high-carbon cropping systems, promoting climate-friendly livestock production systems, protecting existing carbon stores in natural forests and grasslands, and restoring vegetation in degraded areas. The chapter [PDF] forms a useful primer in eco-agriculture (not that you don’t know all about those techniques already).

The report largely avoids the debates over the flashpoints of nuclear energy and carbon sequestration, devoting more ink to renewables, chiefly wind and solar: “Renewable energy combined with energy efficiency can do the job, and renewables are the only technologies available right now that can achieve the emissions reductions needed in the near term.”

In using phrases like “a multicentury commitment to action,” the report sounds pretty lofty, as if climate change were chiefly an academic puzzle, not a messy political one. But sections on the urgency of international climate meetings and on the problem of making climate action fair to developing nations put the report’s prescriptions into a helpful context. If parts of the report feel like an intellectual exercise, it’s still likely to be useful for those hashing out political plans.