BEIJING Coaxing China into a global grand bargain to fight climate change that also satisfies the United States and other rich nations threatens to be even more daunting and elusive than fixing the economic rifts dividing them.
China is the world's biggest emitter of the greenhouse gases from human activity stoking global warming, having outstripped the United States. Those two powers will play a big part in determining whether climate pact talks in Cancun, Mexico, from November 29 can make progress toward a comprehensive deal.
Their often rival stances have long strained climate negotiations. Beijing and Washington have also recently sparred over China's exchange rate controls and huge trade surplus.
"We talk about looking for big points of agreement and keeping small disputes in check, but Cancun will be about looking for small agreements to keep the big disputes in check," said Zhang Haibin, an expert on international climate change politics at Peking University.
Cancun is meant to take modest yet reassuring steps on the way to a binding agreement. But with Beijing at odds with Washington and other Western powers over the scale and transparency of emissions aims, and the principles underpinning any new deal, even limited success is not a sure thing.
"Ultimately what is at stake for each side is its strategic interests, and that's why even small issues can be so troublesome," said Zhang, the Beijing professor.
"A climate change agreement is about allocating emissions rights, and that involves basic interests in economic growth and the costs of mitigation (of greenhouse gases)," said Zhang.
"With the remaining emissions space so limited, China has a basic interest in preserving its space and expecting more from the developed countries so it can ensure its right to develop."
Intense negotiations last year failed to agree on a binding treaty and culminated in a rancorous meeting in Copenhagen.
Failure at Cancun could deepen discord between advanced and developing economies, especially between the U.S. and China, which between them emit 43 percent of the world's carbon dioxide, the main greenhouse gas from burning coal, oil and natural gas.
Global emissions are already approaching levels that many scientists believe make dangerous climate change hard to avoid, auguring more extreme weather, crop failures and rising seas.
"It is scientifically impossible to address climate change without meaningful greenhouse gas reductions from both countries, therefore the positions that these countries take in the negotiations are closely watched by countries around the world," said Joanna Lewis, an expert on U.S.-China climate and clean energy ties at Georgetown University in Washington D.C.
Negotiators hope to agree in Cancun on funds to help poor nations to cope with climate change, steps to protect forests that absorb carbon dioxide, and other building blocks of a binding agreement that negotiators hope to reach late next year.
China is now probably the world's second biggest economy, having passed Japan. Yet China's average emissions per person are still below the industrialized countries', and Beijing says it is unjust to focus on total emissions to determine climate obligations.
"The cost estimates for coping with climate change are growing, and China still needs funds and technology to address the opportunities foregone from paying for that," said Zou Ji, the China Country Director of the World Resources Institute, a Washington D.C.-based group that advocates climate change action.
Beijing's main goal in Cancun, however, will be defensive: warding off demands for it to put its emissions under stricter treaty obligations.
China's emissions have more than doubled since 2000 and they grew about 9 percent last year. That growth is set to continue for many years, and is stirring demands for Beijing to spell out in a treaty how it will control and ultimately cut them.
Beijing has made a domestic vow to reduce "carbon intensity," the amount of carbon dioxide emitted for each dollar of economic growth, by 40-45 percent by 2020 compared to 2005. But it says that goal will not be turned into a binding international target that it fears could hinder development and autonomy.
TOPPLE THE KYOTO TOWER?
Beijing instead wants to keep as the pillar climate treaty the Kyoto Protocol, under which nearly all rich countries agreed to legally binding emissions goals, with the big exception of the United States, which refused to become a party.
Under Kyoto, poorer nations, including China, take voluntary, non-binding steps to curb the growth of emissions while they focus on development and lifting citizens out of poverty.
The United States and other rich nations want a new global deal to discard that either-or division.
That could make for tense talks in Cancun.
"The issues about the Kyoto Protocol are now the most contentious issues in climate change negotiations and the biggest obstacles blocking scheduled progress," Huang Huikang, the Chinese Foreign Ministry's special representative for climate change talks, told a news conference last week.
"There's absolutely no need to topple that tower and start building over again," he said.
(Editing by David Fogarty)