US Delegation’s Carbon Figures Check Out, But Mask Divides

By Andrew Freedman

(See Climate Central's supporting calculations for this article.)

During the Copenhagen climate summit, the U.S. delegation has gone to great lengths to defend its targets for reducing greenhouse gas emissions, which, according to critics, lag behind many industrialized countries. During the past several days, various U.S. cabinet members have rotated through the sprawling Bella Center here to tout American actions, but the U.S. continues to be criticized by other industrialized nations and developing countries, such as China and India, for not committing to more stringent emissions cuts.

At a press conference yesterday, U.S. Climate Change Special Envoy Todd Stern rebutted charges that the American emissions targets are not stringent enough by reciting a slew of data intended to prove the point that American commitments are on par or more ambitious than other industrialized countries. Unfortunately for the press, Stern did not hand out a cheat sheet explaining the data, so with help from Climate Central scientists, here is a summary and assessment of Stern’s numbers.

Stern presented six ways to express the U.S. emissions reduction targets, also known as mitigation targets. He indicated percentage reductions in future years for:

  1. Total emissions relative to the 2005 level of emissions.
  2. Total emissions relative to the 1990 level of emissions.
  3. Total emissions reductions relative to a “business as usual” future
  4. Reductions in average per-capita emissions relative to 1990 levels
  5. Reductions in average emissions per $ of gross domestic product (so-called “carbon intensity”)
  6. Reductions in atmospheric concentrations of greenhouse gases.

According to Stern, U.S. targets are equal to or more ambitious than many other developed countries for five out of the six metrics. (He indicated that #2 above is the only one where the U.S. falls short.)

“I frequently … am asked about issues of comparability between the US and other developing countries, and I frequently say that our numbers are quite comparable by any numbers of measures,” Stern told reporters.

According to Climate Central scientists, Stern’s metrics putting U.S. goals in perspective check out in all four cases where an assessment is possible: list items 1, 2, 4, and 5 (see calculations here). Items 3 and 6 could not be evaluated based on the information Stern supplied.  Now, point by point in more detail:

1 and 2. Stern said the U.S. was proposing greenhouse gas emissions reductions of about 17% by 2020 and 42% by 2030, relative to 2005. The last number corresponds to a 33% reduction compared to a 1990 baseline. The US proposals are consistent with congressional legislation that has passed the House, and is pending in the Senate.

Stern compared these reduction targets with EU targets for 2020 proposed at COP15, which he said amount to a 13% reduction relative to 2005 and a 20% reduction relative to 1990. He acknowledged and praised the reductions that the EU has already made (based on their commitments under the 1997 Kyoto agreement), while noting that the U.S. goal of 17% reduction relative to 2005 is more aggressive than the EU target.

While it may seem like techno-speak, the question of baseline year is important, because the Kyoto Protocol used the 1990 baseline, when U.S. emissions were 6.148 Gigatons of carbon dioxide equivalent – much lower than the 7.130 Gigatons emitted in 2005 (data from the EPA). Most countries that have ratified and implemented Kyoto want to keep that 1990 baseline, rather than shift it to a later period. The United States signed but never ratified Kyoto, and it is adamantly opposed to the 1990 baseline.

The disagreement about baseline year stems from the fact that nations that implemented Kyoto have generally been working already to reduce emissions. A 1990 baseline would recognize those efforts: they would count toward achieving the ultimate goal. At the same time, a 2005 baseline would benefit any nations that did not work as hard to reduce emissions prior to 2005, and which therefore had relatively high emissions then. The idea is that these countries can now take large steps more easily by harvesting the “low-hanging fruit” of emissions reductions that other nations already tackled before 2005. Many countries that participated in the Kyoto Protocol therefore say that using a 2005 baseline would benefit the United States to the detriment of others.

“I would say that it’s only in the hermetically sealed world of global climate change negotiations that a baseline year of 1990 to measure the reduction of emissions from now until 2020 would be treated as sacrosanct,” Stern said.

3. Relative to a ‘business as usual’ future (with little or no effort made to reduce emissions), Stern claimed the U.S. target for 2020 would represent a reduction of 17%. He said this would be larger than for the EU (estimated to be 12%) and Japan (10%), though not as large as Australia (20%).  This metric is difficult to assess, since Stern did not indicate what “business-as-usual” emissions trajectories were assumed.

4. He observed that the U.S. reduction target for 2020 on a per capita basis was more aggressive than the EU’s even when compared to the 1990 level (29% for the US versus 25% for the EU). His comments suggested that this metric would favor the U.S. even more if 2005 were taken as the baseline.

5. The proposed reduction in carbon intensity, which is a measurement of the ratio of greenhouse gas emissions per unit of economic output (GDP), is “in line with” those of the EU and other developed countries proposals, according to Stern. Climate Central calculations confirm this.

6. Stern claimed that U.S. targets would achieve more than a 3 fold greater reduction in atmospheric concentration of CO2 than other developed country targets would achieve, even accounting for different starting points.  Climate Central scientists could not assess Stern’s claim in part because he did not explain exactly what he meant by “accounting for different starting points.”