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quently not adopted by Congress. The pack. age contained many conservation and energy-efficiency measures. The elimination of these programs in the updated baseline raises projected emissions by about 4 MMTCE.
Congressional action on fiscal year 1996 appropriations has also affected the baseline (as well as the effectiveness of actions dis. cussed later in this section). Assuming congressional cuts of ongoing government energy-efficiency programs are continued, carbon emissions will increase by another 7 MMTCE in 2000. A component of this is a reduction in DOE's Weatherization Assiscance Program and Federal Energy Management Program, which increase projected emissions in 2000 by 2.5 MMTCE.
Emission Accounting Changes. Subsequent to issuance of the 1993 CCAP, international guidance for consistent reporting of national emission inventories was developed. To maintain consistency with these guidelines, the 1997 CAR excludes emissions resulting from the combustion of international bunker fuels (fuels delivered to marine vessels, including warships and fishing vessels, and aircraft used for international transport). This change reduces estimated carbon emis. sions in 1990 by 22 MMTCE and projected carbon emissions in 2000 by 27 MMTCE. Because emissions from international bunkers are projected to be larger than the quantity estimated for 1990 historical usage, adoption of the agreed methodology that excludes these emissions reduces the projected growth in emissions by 5 MMTCE relative to the methodology used in the 1993 CCAP.
Projected Baseline for Methane and
Greenhouse gases other than carbon dioxide—such as methane, nitrous oxide, halogenated and perfluorinated compounds (HFCs and PFCs), and sulfur hexaflouride (SFs/comprised more than 15 percent of U.S. greenhouse gas emissions in 1990. Important information affecting the baseline emission estimates for these gases has become available since issuance of the original 1993 CCAP.
New projections of HFC emissions have been developed based on more recent infor. mation about the production and use of substitutes for chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) being phased out under international obligations to protect the stratospheric ozone layer. This modification, together with a slight revision for 1990 estimated emissions (-3 MMTCE), increase the projected growth in HFC emissions from 1990 to 2000 by about 7 MMTCE.
The inclusion of additional halogenated gases (i.e., SF.. NF,. and CHF,), as well as the identification of nitric acid production as a new source for nitrous oxide, increases baseline growth in greenhouse gas emissions from 1990 to 2000 by about 6 MMTCE.
The IPCC has revised the global warming potentials (GWPs) used to express emissions of other gases in carbon-equivalent terms (Table 4-9). Thus, a fixed amount of emissions of a greenhouse gas other than carbon dioxide is now believed to make either a larger or a smaller contribution to global warming
The 1993 CCAP had projected noncarbon greenhouse gases to increase by about 6
sources. This baseline after the year 2000 is consistent with recent trends in U.S. methane emissions, which have increased by 4 percent over the last five years. During this period, methane emissions from coal mining have fluctuated with changes in production levels at eastern U.S. coal mines, including a major coal strike in 1993. The net result of the change in the baseline assumptions is an increase of about 11 MMTCE for methane emissions in the year 2000 compared to the 1993 CCAP
21 310 6,500 9.200 11.700
• The GWP volues reported here reflect contnbutions to rodoove forong over 100 years The IPCC also reports GWPS for 20and 500 year periods.
MMTCE in the baseline between 1990 and 2000. The current baseline estimate projects these gases to increase by about 34 MMTCE. Together, these changes are estimated to increase the overall growth in greenhouse gas emissions from 1990 to 2000 by about 28 MMTCE. The revised baselines for methane, nitrous oxides, and HFCs and PFCs follow.
Methone Emissions. The primary U.S. sources of methane emissions are landfills, domesticated livestock, coal mines, and natural gas systems. The baseline forecast for methane has been revised from a decrease of about 15 MMTCE to a decrease of about 4 MMTCE from 1990 to 2000. Most of the changes in baseline projections are due to an increase in some methane sources, particu. larly agricultural methane emissions. As a result, baseline methane emissions are projected to comprise about 10 percent of U.S. greenhouse gas emissions in the year 2000.
Similar to what was envisioned in the 1993 CCAP baseline, EPA issued a final landfill rule in 1996 that will cut methane emissions in half by 2000. The landfill rule more than offsets expected growth from the other
Nitrous Oxide Emissions. Baseline N, O emis-
from fertilized soils has been revised
NO emissions in the baseline are projected to remain at 1990 levels in 2000. Emissions were projected to decrease by 4 MMTCE in the 1993 CCAP. N, O emissions have increased only slightly over the last five years, although 1994 shows significantly higher emissions from fertilizer use, as farmers planted more acreage and increased fertilizer use to replace nutrients lost in significant flooding that occurred in 1993. In the future, emissions from fertilizer use should return to prior levels, and the results of industrial emission-reduction activities should become apparent.
HFC ond PFC Emissions. Hydrofluorocarbons (HFCs) and perfluorinated compounds (PFCs) are emitted in certain industrial applications and are being introduced as alternatives to the ozone-depleting substances phased out under the Montreal Protocol and Clean Air Act Amendments of 1990. These gases are projected to represent about 3 per. cent of U.S. greenhouse gas emissions in the year 2000, but emissions are projected to increase as their use as alternatives to ozone. depleting substances increases. The major source of HFCs is currently a by-product of HCFC-22 production, and the major source of PFCs is currently aluminum smelting.
New information about emissions of HFCs and PFCs since the 1993 CCAP increases the estimated baseline growth of greenhouse gas emissions from 1990 to 2000. The major changes include: • Emissions from HFCs used as substi
tutes for CFCs are now expected to grow from negligible levels in 1990 to about 31 MMTCE in 2000, instead of the 23 MMTCE estimated
for 2000 in the 1993 CCAP. • Emissions of HFC-23, a by-product of
HCFC-22 production, are expected to grow by about 3 MMTCE between now and 2000 and remain constant after that at about 15 MMTCE. HEC
23 was expected to grow by about 2
MMTCE in the baseline 1993 CCAP. • PFC emissions from aluminum smelt.
ing stay constant at about 5 MMTCE
MMTCE by 2000.
increase the growth of HFC and PFC
The growth in baseline emissions of HFCs and PFCs is beginning now and can be expected to continue through 2000 and beyond.
Projected Baseline for
The new baseline projections by USDA's Forest Service show decreasing annual carbon sequestration in U.S. forests from 1990 to 2000, compared to a slightly increasing sequestration rate in the original 1993 CCAP (see Table 4). The change in baseline reflects several developments: į Estimated net forest growth in the
Northeast is declining as the age of
baseline carbon sequestration rates
The net effect of changes to the forest carbon sequestration baseline has been to increase greenhouse gas emissions by 23 MMTCE compared to the 1993 CCAP baseline.
Integrated Analysis of
Growth in Emissions Between 1990 and 2000
Softwood removals in the South,
exceed growth in all southern states. • Reduced harvests in national forests
in the West will increase carbon stor-
The latest Forest Service projections indicate a small reduction in total forest land because of continued net losses to nonforest use. While there was a small increase (one per. cent) in forest land between 1987 and 1992, this trend is expected to reverse because of losses to urban uses and because federal treeplanting programs for private landowners have experienced funding reductions. i Reduced funding for the Forestry
Incentives Program is reflected in the new baseline sequestration estimate for 2000 (125 MMTCE in 1990 and 109 MMTCE in 2000). FIP accounted for about 175,000 acres of
tree planting annually in the past. · The Agricultural Conservation Pro
gram was terminated in the 1996 Farm Bill. Active since 1936, in fiscal year 1994 ACP planted more than 12,140 hectares (30,000 acres) of trees. The net effect of reduced fund. ing for FIP and ACP termination is that tree planting under federal pro. grams is likely to decrease by 60,704 hectares (150,000 acres) or more annually. It is unlikely that new private tree planting will offset this
impact • The Forest Service Stewardship
Incentive Program's tree-planting budget has also been cut, lowering
Drawing on the review of individual actions presented in the first part of this chapter, this section presents aggregate emission reductions for the revised 1997 CAR. It then combines these projections of program impacts with the baseline information in that previous section to project emission levels for 2000. To facilitate comparisons, results are reported using the same groupings as in the 1993 CCAP
As noted in the 1993 CCAP, the aggre. gate analysis of energy-related actions requires special attention, given the potential for significant interplay among actions, and between actions and the baseline. The updated aggregate action impact projections presented in this section reflect an integrated analysis of energy-related actions developed using the Integrated Dynamic Energy Analy. sis Simulation (IDEAS) model, the same tool used in the earlier analysis. Because many of the foundation actions include in their announced plans a substantial number of measures that also fall within the broad set. ting of other actions or baseline assumptions, particular care was taken to avoid doublecounting within this analysis.
The sharp reductions from Administration funding requests in appropriations bills enacted by Congress for fiscal year 1996 and 1997 would, especially if continued in future years, have a severe adverse effects on projected greenhouse gas emission levels in 2000 and beyond: (1) reductions in resources avail. able to implement actions significantly diminish projected emission-reduction bene fits in 2000 and (2) funding cuts in base renewable research and development and energy-efficiency programs can have potentially large impacts on emissions beyond 2000.
The Administration has consistently requested the funding needed to ensure climate change actions would contribute to U.S. policies to reduce greenhouse gas emissions. However, recent shortfalls in program funding have severely limited the nation's ability to reduce greenhouse gas emissions. A qualitative estimate of this impact suggests that reduced funding is responsible for about a 30–40 MMTCE decrease in overall savings
in 2000 that could have been realized if fund. ing were provided in the 1993 CCAP.
The updated "point estimate" of growth in emissions of 188 MMTCE between 1990 and 2000 in the current funding case reflects the combined effect of many changes from the 1993 CCAP, which projected a decrease of 2 MMTCE over the same period. Table 4-10 summarizes the factors contributing to the changing estimate of the emissions gap in the year 2000
Nonetheless, climate change actions have produced measurable reductions in greenhouse gas emissions and could produce much more in the years to come if current funding levels are maintained. Table 4-11 reports the net reduction of projected actions' performance for the years 2000, 2010, and 2020. The 1993 CCAP perfor. mance projections are also provided to facili. tate comparisons. The discussion that follows outlines the key forces driving differences
The overall reductions in this column would be even larger if foundation actions were not induded here as in the 1993 CCAP.