Some of the world’s top climatologists, under the collective title of the Global Carbon Project, have released what is widely considered the definitive accounting of the greenhouse-gas emissions situation. And the news is, as you might expect, not good. Nature’s Climate Feedback bloggers sum it up as “We’re all doomed.” The full report is a lot to swallow, but here’s what policy makers and anyone thinking of casting a vote in either the Canadian election next month or the American election in November should know:
Anthropogenic CO2 emissions are growing x4 faster since 2000 than during the previous decade, and above the worst case emission scenario of the Intergovernmental Panel on Climate Change (IPCC).
The efficiency of natural sinks has decreased by 5% over the last 50 years (and will continue to do so in the future), implying that the longer it takes to begin reducing emissions significantly, the larger the cuts needed to stabilize atmospheric CO2.
All these changes have led to an acceleration of atmospheric CO2 growth 33% faster since 2000 than in the previous two decades, implying a stronger climate forcing and sooner than expected.
Barry Brook, director of the Research Institute for Climate Change and Sustainability at the University of Adelaide in Australia tells Reuters that this means “CO2 concentrations could hit 450 ppm by 2030 instead of 2040 as currently predicted.” Keep that in mind when examining the candidate’s emissions-reductions proposals. If Brook is correct, none of the schedules, not even Canada’s Green Party plan, are sufficient to avoid hitting 450.
And here are two of the most important graphs from the report. The first measures carbon emissions in petagrams, but 1 Pg = 1 billion tonnes, which is how such figures are usually delivered in popular reports.
The second describes the other really troubling trend: the ability of the oceans to absorb CO2, as a fraction of the total emissions. Again, things are worse than previously feared.
It is impossible to resist repeating the phrases “above the worst case emission scenario” and “sooner than expected.” If you’re willing to get more depressed, there are lots more of that kind of thing in a PDF of the project’s summary PowerPoint.