CANCÚN, Mexico – There might have been some hope among parties seeking a new international climate agreement that sunny skies and azure seas would brighten treaty negotiations after the darkness and chill of Copenhagen one year ago.

But just two days into the two-week treaty conference here, gloom has already spread among climate campaigners and treaty supporters.

The main source this time is Japan.

With unusual bluntness, senior Japanese officials have said their country will not seek any extension beyond 2012 of the gas restrictions set under the Kyoto Protocol, the first (and possibly last) international pact with mandatory restrictions on greenhouse gases.

[ The Guardian provides an even more definitive statement from a senior Japanese official: “Japan will not inscribe its target under the Kyoto protocol on any conditions or under any circumstances.” ]

In an interview with a Bloomberg reporter on Tuesday, Kuni Shimada, the special adviser to Japan’s environment minister, stated the issue with crystal clarity:

“Without the active participation of the two biggest emitters, namely China and the United States, it’s not a global effort,” said Shimada, who was formerly Japan’s lead negotiator at the talks. “Whatever happens, under any kind of conditions we do not accept a second commitment period.”

For industrialized countries and China, the demand for all to step forward on gas restrictions in any new agreement is as much about competitiveness as climatology. For years, it’s been clear that real-time economic realities still trump emerging climate concerns.

Kyoto has long been seen as a dead end, given that, for different reasons, both China and the United States, the world’s dominant sources of greenhouse-gas emissions, are not bound by the pact. And Japan had signaled this move for a long time, as well.

But Japan’s statements still jarred the negotiations, a realm where language without caveats [or brackets] is a rarity.

The protocol is extremely important to dozens of developing countries that have received substantial sums for emissions credits earned under the agreement’s Clean Development Mechanism. They’ll never sign a new global accord unless those money flows are sustained (on top of tens of billions of dollars being sought to help poor countries adapt to human-driven climate change).

Japan’s position on climate and related concerns is important not only because of its still-substantial role in the global economy, but also because it hosted talks that, with much fanfare, produced the Kyoto agreement in 1997.

All industrialized countries except the United States ratified the treaty and are bound, at least on paper, by the protocol’s gas restrictions through 2012. No developing countries, not even emerging the superpower and super-emitter China, have emissions limits under that pact.

Most efforts here are aimed at creating a new global agreement including commitments on emissions from the United States and China. But the fate of Kyoto will powerfully influence those negotiations.

One of the best barometers of prospects here lies elsewhere, in the carbon markets. BusinessWeek’s excellent roundup of developments in the talks, and their implications, notes the widening spread between the value of a ton of avoided greenhouse emissions in European carbon markets, which the European Union has committed to perpetuating, and credits under the troubled Kyoto mechanism.

The magazine reported World Bank data showing that the global market in Kyoto credits dropped by more than half from 2008 to 2009, when $2.7 billion flowed.

I rounded up reactions to Japan’s move from environmental campaigners who are known for putting the best possible spin on things and here’s what they

Alden Meyer, Union of Concerned Scientists —

Not really much new here — they’ve been putting this message out for a while now. But the stridency of the Japanese intervention yesterday took folks by surprise.

David D. Doniger, Natural Resources Defense Council —

It does seem quite emphatic and forceful (which is not Japan’s usual style), but in my view, Japan (and other developed countries) have been clear for several years that they need action commitments by the U.S. and big developing countries before making new action commitments of their own. The structure of the Copenhagen Accord recognized the need for action by all the big emitters, though it kept a differentiation – a less rigid one than Kyoto – between the character of the developed and developing country commitments. There are two annexes, and the action commitments of developing countries have a less “legally binding” character than those of the developed countries. Still, as indicated above, the differences are less rigid than Kyoto’s, under which the big developing countries had no specific obligations at all, and Japan is stating the obvious that they won’t perpetuate that.

Postscript:

Another source of discussion here has been some revelations from the Wikileaks files about State Department discussions of Saudi Arabia’s efforts to block treaty progress. In this case, at least, there’s really not much there there, considering how clear Saudi Arabia’s position has been in treaty talks over the last 20 years. For more on that, review my 2009 post, ‘Striving for No’ in Climate Talks.

Also on the Wikileaks front, a bunch of commentators have complained about a double standard at The Times for publishing these files while not posting the cache of University of East Anglia e-mail messages and files that spread around the Web one year ago. I can’t speak for the paper, of course, but I updated the relevant Dot Earth post with my views on my coverage.