Humans are fast running out of time to avoid climate change's worst consequences, says a new report from the United Nations Environment Program, and delayed action will be costly down the road.
The international community has pledged to limit temperature rise this century to 2 degrees Celsius, but even current emissions cutbacks don't put Earth on pace to meet target levels by 2020, the report says. Failing to meet the 2020 goals "will mean much higher rates of global emission reductions in the medium term; greater lock-in of carbon-intensive infrastructure; greater dependence on often unproven technologies in the medium term; greater costs of mitigation in the medium and long term; and greater risks of failing to meet the 2° C target."
The U.N. says carbon emissions will have to drop to 44 gigatons by 2020 to avoid serious problems. Emissions are currently on pace to exceed that by 8 to 12 gigatons. Still, the U.N. expressed hope that the goal could still be met. "Even though the window of opportunity is narrowing, it is still possible to attain the 2020 goal ... through firm and rapid action," said the report.