Monday, negotiators at the Cancun climate summit got down to brass tacks, settling into “vast, sunless meeting rooms, intent on restoring the credibility of a process aimed at slowing global warming.”

There were the usual moments of comic relief, including the removal of professional climate skeptic Christopher Monckton from a corporate lunch, and two apparent early victories in negotiations between the U.S. and China.

China appears ready to accede to U.S. demands that it should allow verification of its emissions, and China made a pledge the U.S. is in no position to make: that its carbon emissions targets will be binding as a U.N. convention.

This pledge, also made last year at Copenhagen, would see China reduce the “carbon intensity” of its economy — that is, the amount of carbon it emits per unit of GDP — by 40 to 45 percent of 2005 levels by 2020.

Some called China’s pledge a “game changer” for a country aiming for “redemption” at Cancun, but U.S. Special Envoy on Climate Change Todd Stern said the pledge was nothing more than “business as usual.” Assistant Chinese Foreign Minister Liu Zhenmin confirmed Stern’s analysis, denying the country had softened its stance on its own emissions.

Japan says no to Kyoto Protocol: Last week, Japan shook up the conference by announcing its opposition to the extension of the Kyoto Protocol, the targets of which would have represented a 29 percent cut in emissions versus the levels expected for 2010, for signatory countries. The Washington Post explains the reasoning behind the surprise announcement — Japan is no longer willing to lower its own emissions, to the detriment of its economy, while the U.S. and China sit idly by.

Meanwhile, China, India, Brazil, and South Africa opened the meeting by pushing the U.S. to pledge deeper emissions cuts than its Copenhagen pledge of 17 percent by 2020 based on 2005 levels, which represents “a zero reduction from 1990, the baseline for Kyoto, according to India Environment Minister Jairam Ramesh.”

The good news about Cancun: While no one expected the U.S. to make deeper cuts at Cancun in light of the domestic appetite for climate legislation, as the talks approached their Friday close, negotiators made progress in a handful of areas, including deforestation, which currently accounts for roughly 15 percent of the annual global greenhouse gas emissions.

Other areas in which negotiators made headway included a compromise text released by India proposing a system for monitoring greenhouse gas emissions cuts and a European Union pledge toward a global fund to finance adaptation and mitigation efforts in the developing world.

… And the persistent disconnect between negotiations and scientific reality: Taking the temperature of the negotiations as a whole, U.N. Secretary General Ban Ki-moon pointed out the obvious: When compared to the demands for emissions reductions, made apparent by the science of climate change, progress at the conference has been insufficient and “business as usual cannot be tolerated, for it would condemn millions — no, billions — billions of children, women, and men around the world to shrinking horizons, and smaller futures.”

Two former U.S. State Department officials reiterated the oft-heard claim a global climate pact is unrealistic and should be abandoned.

Is the U.S. going to pay for the damage it did to the climate?: Farrukh Iqbal Khan, chair of the Adaptation Fund, tells Kate Sheppard of Mother Jones that as more and more countries face devastating impacts worsened by climate change, as Pakistan did with its recent floods, they are increasingly finding themselves helpless to do anything about it.

Four Republican senators don’t want the U.S. to direct money to the U.N. climate adaptation fund, even as companies including Starbucks and Nike argued the U.S. should take the lead in doing just that.

Emissions regulations to go before the U.S. Supreme Court: An earlier lower court ruling allowing states to sue emitters of greenhouse gas emissions for creating a “public nuisance” set up an important test of whether or not the courts can be used to penalize those who contribute to climate change. It’s therefore notable the U.S. Supreme Court has agreed to hear an appeal of that ruling by four power plant companies.

In Congress, is “clean” energy the new “renewable”?: United States Secretary of Energy Steven Chu said at a nuclear energy summit Tuesday the Obama administration might be amenable to including nuclear power in future energy legislation, expanding, in an apparent attempt at bipartisanship, the concept of domestic and climate-friendly energy sources beyond renewables.

The Climate Post offers a rundown of the week in climate and energy news. It is produced each Thursday by Duke University’s Nicholas Institute for Environmental Policy Solutions.