By Janet Raloff

Web edition: July 9, 2008

Last month, the U.S. National Academy of Sciences and 12 counterparts in other nations jointly called on world leaders who would be attending the G-8 Summit in Japan, this week, “to limit the threat of climate change.” Well, those leaders did pledge to do something — just not much.

Our President and his fellow attendees “embraced for the first time . . . an ambitious but nonbinding goal of slashing greenhouse-gas emissions in half by mid-century,” according to an Associated Press account in today’s paper. But what good is a nonbinding goal? It sounds like a Christmas wish list.

These leaders should have issued some moral-equivalent-of-war imperative (to borrow from Jimmy Carter) promising that the world’s biggest, richest, and most polluting nations (all of which were represented at the meeting) would absolutely cut emissions dramatically, come hell or high water.

I know, with the exception of the United States, all G-8 members (which also include Canada, France, Germany, Italy, Japan, Russia, and the United Kingdom) have signed onto the Kyoto Protocol. And this United Nations treaty mandates greenhouse-gas-emissions reductions. However, the reductions required are country specific and small — less than 10 percent below a nation’s 1990 emissions. And the deadline: Four from years from now.

The European Union has promised to do more: cut its emissions 20 percent below 1990 values within the next 12 years. The EU also offered to go further —drop its members’ greenhouse-gas emissions 30 percent below 1990 values by 2030, but if and only if other industrialized nations (read Uncle Sam) would too. To date, the United States has not committed itself to any firm cuts.

Another gimp in the G-8’s announced stride towards slowing climate change is the putative date this group offered for achieving its emissions drop — mid-century. That isn’t nearly soon enough to reliably stave off some pretty dire climatic changes, according to the Intergovernmental Panel on Climate Change. This august body of scientists, who’ve pored over the data to understand just how much wiggle room we might have in timetables for halting devastation, suggests a turnaround in emissions rates must be achieved much sooner. In fact, it has said that emissions growth must be halted within the next decade, and actual drops in emissions must follow immediately afterward.

Another major question mark is what the G-8’s aspirational goal of halving emissions is meant to connote. Is it, as the Kyoto Protocol requires, a drop in the quantity of emissions as compared to what each nation had spewed in 1990? Or a drop to a level 50 percent below current emissions, which would allow a much higher rate of pollution to continue?

Oh, and then there is the issue of which emissions will be tackled. The G-8’s unstated implication is that the proposed emissions drops would only cover those greenhouse gases regulated under the Kyoto treaty (carbon dioxide, methane, nitrous oxide, sulfur hexafluoride, hydrofluorocarbons, and perfluorocarbons). Yet it would make sense to also include any pollutant with a strong greenhouse-warming potential that is emitted in large quantities — such as the nitrogen trifluoride widely used to make flat-screen TVs and computers. Details on this currently unregulated greenhouse gas, with a global-warming potency some 17,000 times that of carbon dioxide, appear in a June 26 paper in Geophysical Research Letters.

Tsk tsk . . . all these are just details to be ironed out.

Big details, actually. Ones slated to be negotiated through the UN Framework Convention on Climate Change. This group’s next meeting takes place this fall, in Poland. At last year’s UNFCCC meeting, its negotiators pledged they would reach some agreement on a successor treaty to the Kyoto Protocol, which is essential because that treaty’s key provisions on emissions-reduction targets and timetables expire at the end of 2012.

Meanwhile the Arctic melts, California risks getting hotter and drier, and crops will probably continue to fail throughout much of Africa and Asia.

We need someone to step in and really shake things up. Someone with no strong allegiance to a particular nation or political ideology. (I know that sounds like some bureaucrat who’d come from the United Nations, except that the UN actually is a very political body.)

What we need is a czar — or czarina — whose foremost allegiance is to the health of the planet and its diverse inhabitants. Anyone care to submit nominees?