U.S. Special Envoy on Climate Change Todd Stern (Photo: Center for American Progress)

At a press briefing yesterday afternoon, Todd Stern, President Obama's Special Envoy on Climate Change at the COP15 climate conference in Copenhagen said that "only in the hermetically sealed world of climate negotiations" is the baseline year of 1990 for measuring emissions mitigation targets treated as "sacrosanct."

Stern then set forth to unpack for journalists how with only the "1990 metric" does the emissions target for the US "look bad."

As a foundation for Stern's remarks, Stern outlined several key points regarding the US commitment on emissions mitigation. The initial target, as reflected in the Waxman-Markey climate bill that passed the House last summer, rests at about a 17 percent reduction over 2005 levels. But Stern explained that target ramps up rapidly from there; by 2025, increasing to a 30 percent reduction over 2005 emission, and jumps again to about 42 percent by 2030. Using 1990 as the reference year, those targets represent an 18 percent and 33 percent emissions cut respectively. Stern said that by that measure, "but only by that measure," is the US reduction target substantially less than that of the EU.

Comparing the EU 20 percent reduction (over 1990) with the US commitment but using the 2005 benchmark for both, the European target drops to 13 percent, less than the 17 percent US commitment, Stern explained.

Using a "business as usual" reference, the the EU's target drops again to 12 percent compared to the 17 percent for the United States. The same business as usual metric reflects a10 percent reduction for Japan and 20 percent for Australia, Stern said.

Using per capita reduction as the reference, Stern explained that even compared to 1990 levels, the US reduction commitment stands at 29 percent, versus 25 percent for the EU.

For carbon intensity, the metric China is using for its target, the US commitment is "a number that is just about exactly in line with the carbon intensity reduction for the EU and other developed countries," Stern explained.

Finally, Stern used the change in atmospheric concentration as a measure to make the point that the current US offer would "reduce atmospheric concentration by about three times more than those proffered by other Annex 1 countries, even if you equalize or account for the different starting point" regarding baseline reference years.

Stern concluded that in "five out of six measures, the US is equal to or higher than the EU or many of our other developed country partners."

Saying he wished no criticism of his partners in other developed countries, Stern also make clear his weariness in "fielding questions all day long from his counterparts" as to why the US isn't doing more.

Given the state of play here in Copenhagen, my guess is Stern and his superiors that are now arriving at COP15 will continue to field those questions.

Image: Center for American Progress via flickr/CC 2.0