	U.S. Greenhouse Gas Emissions and Baselines

Pursuant to the United Nations Framework Convention on Climate Change, the United Stateshas published "national inventories of anthropogenic emissions by sources and removals by sinksof all greenhouse gases not controlled by the Montreal Protocol, using comparable methodologies... agreed upon by the Conference of the Parties." U.S. Greenhouse Gas Emissions (MMTCE),1990-2001 
Source: Environmental Protection Agency, Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2001 (April 2003), EPA 430R03004. (12) The United States also from timeto time reports on emissions andexplains its climate change programs in the Climate Action Report (CAR) to theUnited Nations; the third CAR was published in 2002. (13)
The U.S. baselines for the UNFCCC and the Kyoto Protocol are shown in Table 2 . Table 4. Status of Emissions Relative to Goals

Under the UNFCCC, the United States committed to the voluntary goal of holdinggreenhouse gas emissions at the end of the 1990s to their 1990 levels. However, U.S. emissions in 2000 were 1,921 MMTCE (not counting sinks). Based on the CAR projection that emissions willbe 2,213 MMTCE in 2010, the average annual reduction that would be necessary for theUnited States to meet the Kyoto target of 1,559 MMTCE per year for 2008-2012 would be654 MMTCE per year, or about 30% below the estimated level of "business as usual"emissions. The President's greenhouse gas initiative has the goal of reducing, through voluntary activities, the intensity of net greenhouse gas emissions per unit of economic activity by 18%over the next 10 years; this compares to a projected "business as usual" decline in intensityof 14% for the period -- compared to a decline during the 1990s of about 10% (see Table3 ). (25) At the anticipated increasedrate of intensity decline, total emissions would decline 100 MMTCE below "business asusual" emissions (although the absolute amount of emissions would continue to rise). The Kyoto Protocol also would provide that sinks can be taken into account in calculating a nation's emissions and its reduction obligation. (31)
Historical data show that the United States failed to meet its voluntary commitment under the UNFCCC for returning aggregate emissions at the end of the 1990s decade to the1990 level. Even with the potential for sequestration andemissions trading to reduce domestic reduction efforts, a goal to reverse greenhouse gasemissions trends would represent an extraordinary technical and political challenge for U.S.energy and environmental policy.
This report reviews U.S. emissions of greenhouse gases in the contexts both of domestic policy and of international obligations and proposals. On October 15, 1992, the United States ratified theUnited Nations Framework Convention on Climate Change (UNFCCC), which entered into forceon March 21, 1994. This committed the United States to "national policies" to limit "itsanthropogenic emissions of greenhouse gases," with a voluntary goal of returning "emissions ofcarbon dioxide [CO 2 ] and other greenhouse gases [methane (CH 4 ), nitrous oxide(N 2 O),hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulfur hexafluoride (SF 6 )]" at the "endof the decade" to "their 1990 levels."
Subsequently, in the 1997 Kyoto Protocol to the UNFCCC, the United States participated in negotiations that ended with agreement on further reductions that could become legally binding. TheUnited States signed the Kyoto Protocol in 1998, but President Clinton did not send it to the Senatefor advice and consent. President Bush has said that he rejects the Protocol, and former U.S.Environmental Protection Agency Administrator Christine Todd Whitman told reporters that theAdministration would not be pursuing the UNFCCC commitment either. Instead, President Bushhas proposed to shift the nation's climate change program from a goal of reducing emissions per seto a goal of reducing energy intensity -- the amount of greenhouse gases emitted per unit ofeconomic productivity. Under the proposal, the intensity, which has been declining for a numberof years, would decline 18% between 2002 and 2012, as opposed to a 14% projected "business asusual" decline.
Meanwhile, the UNFCCC "end of the decade" deadline has passed and U.S. greenhouse gas emissions continue on an upward trend, though with dips in 1991 and in 2001, attributed mostly toeconomic slowdowns. Based on historical data, 2001 emissions were about 13% in excess of theUNFCCC goal. Overall, from 1990 to 2001, U.S. greenhouse gas emissions (weighted by globalwarming potential) have increased an average of about 1.1% per year. Projections suggest that U.S.emissions will continue to rise for at least the next decade. Reversing the upward trend ingreenhouse gas emissions would represent an extraordinary technical and political challenge to U.S.energy and environmental policy.
This report will be updated as necessary.