By Janet Raloff, for Science News' Science & the Public Blog
There are 33 days until the opening of formal negotiations in Copenhagen on the next global climate-protection treaty. The hoped-for accord would take up where the current treaty leaves off. But to get some perspective on just where that is, a new United Nations report describes for negotiators and the public just how much the Kyoto Protocol has achieved.
And it shows that real strides have been made in slowing the growth of greenhouse-gas emissions, thanks to many European nations (albeit with little help from their North American cousins or Japan).
Still, society remains a long way from arresting atmospheric growth in greenhouse gases—especially because only 40 of some 190 U.N. member nations were mandated under the Kyoto treaty to make emissions cuts. Chief among those not on the list: China, now the global leader in greenhouse-gas emissions.
Under the Kyoto Protocol, which was negotiated in 1997 (and implemented seven and a half years later), the world’s developed or industrialized nations—the so-called Annex I countries—were by 2012 supposed to have permanently cut their releases of carbon dioxide and other greenhouse gases to five percent below each country’s 1990 levels.
It takes a while, typically two years, for each nation to tally these and report the values back to the United Nations. So the Oct. 21 advance version of the tally covers emissions only through 2007. It shows that greenhouse-gas releases from Annex I nations were roughly equivalent to a little more than 18 gigatons (billion metric tons) of CO2. That’s about 4 percent less than in 1990—a drop equivalent to 80 percent of what has been called for under the treaty.
Which is good news. Sort of.
Many countries that cut their emissions dramatically didn’t do so deliberately, however. For instance, the widespread economic depression that hit former Soviet bloc nations over the past two decades has also depressed their industrial output. So greenhouse-gas emissions from their dirty factories, power plants and traffic have fallen — in come cases like a lead balloon. One can be fairly sure that if their economies rebound, so will their greenhouse emissions.
This table shows how Annex I countries compared in greenhouse emissions, as reported to the United Nations. Those color coded in red are the big emitters, countries still spewing in excess of half a gigatons of CO2 each year. Those colored blue emit around 50 megatons a year or less. Greenhouse emissions by nations colored yellow fall in between those two extremes.
The new U.N. report also points to where the biggest emissions reductions have occurred. And you might be surprised by the answer: agriculture.
At about 15 billion metric tons of CO2 (or its equivalent), the energy sector dwarfs agriculture—by roughly 10 fold. Yet the actual greenhouse-gas reductions by agriculture—0.34 gigatons, which are small in an absolute sense—still exceed by 50 percent the improvements made by the colossal energy sector.
Again, details aren’t available for what happened, but it’s certainly conceivable that some developed nations paved over farmland to industrialize more heavily, or developed once-rural outskirts (what we politely refer to as sprawl). In such cases, farms may not have gotten cleaner, just smaller.
Certain energy-intensive sectors of the economy, the U.N. report shows, experienced mixed success in cutting emissions. For instance, those from manufacturing and construction fell by almost 12 percent between 1990 and 2007; fugitive greenhouse emissions from industrial processes dropped almost 16 percent. But together, their starting emissions had only totaled some 3.7 gigatons.
Over the same period, transportion-related greenhouse emissions soared nearly 18 percent, to 3.8 gigatons, and emissions by energy industries increased 5.6 percent, to more than 6 gigatons.
Bottom line, much of the Kyoto Protocol’s emissions-reduction goal has been achieved, helped along by the recession.