Washington Greenhouse Gas Emissions and Sinks Inventory Summary Washington Greenhouse Gas Emissions for 1990

WASHINGTON GREENHOUSE GAS EMISSIONS AND SINKS INVENTORY:

SUMMARY

Washington Greenhouse Gas Emissions for 1990

Million Metric Tons of Carbon Equivalent

Total Energy Waste Agriculture Industry Land Use

Sector

~ carbon
equivalent

The report "Greenhouse Gas Emissions Inventory for Washington State, 1990' provides
a detailed inventory of greenhouse gas emissions and sinks for Washington in 1990.
Emissions were estimated using methods from EPA's 1992 guidance document State
Workbook: Methodologies for Estimating Greenhouse Gas Emissions. In 1990,
Washington emitted 17.0 million metric tons of carbon equivalent (MMTCE).

Washington estimated emissions of 2.4 MMTCE from biomass fuels and from other
sources not included in the workbook. Emissions from these sources are not included in
the reported total or the table below.1

The principal greenhouse gases were carbon dioxide, comprising 47.2 million metric
tons (12.9 MMTCE), and methane with 0.4 million metric tons (2.4 MMTCE). Other
emissions included 800 metric tons of perfluorocarbons (1.5 MMTCE), and 0.003 million
metric tons of nitrous oxide (0.2 MMTCE).

1 Note that the state of the art emission inventory method has advanced since Washington
completed its inventory; therefore, we have made the following adjustments to Washington's
emission estimates. First, we excluded emission estimates for sources not covered by the most
recent inventory guidance (http://www.epa.gov/ttnchie1/eiip/techrep.htrrtfareen). These
emissions include carbon dioxide from decomposition in landfills and from methane flaring at
landfills, and methane from wetland drainage. Second, we used updated carbon coefficients for
some fuel types. Third, we used updated values for global warming potentials.

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Washington Greenhouse Gas Emissions for 1990

BY SECTOR

C02
(MMTCE)

Methane
(MMTCE)

Nitrous Oxide
(MMTCE)

HFCs, PFCs,
and SF6
(MMTCE)

Total GHG
Emissions
(MMTCE)

Energy - Residential

1.0

*

*

*

1.0

Energy - Commercial

1.0

*

*

*

1.0

Energy - Industrial

2.4

*

*

*

2.4

Energy - Transport

11.7

*

*

*

11.7

Energy - Utility

2.3

*

*

*

2.3

Energy - Exported Electricity

*

*

*

*

*

Energy - Other

*

0.1

*

*

0.1

Total Energy

18.4

0.1

*

*

18.4

Waste

*

1.6

*

*

1.6

Agriculture

*

0.8

0.2

*

1.0

Industry

0.3

*

*

1.5

1.8

Land Use

-5.8

*

*

*

-5.8

Total

12.9

2.4

0.2

1.5

17.0

All emissions are reported in million metric tons of carbon equivalent (MMTCE).

An asterisk ( * ) indicates that emissions of the gas from this sector were zero, insignificant, or not reported.

Emissions due to coal mining and extraction of natural gas and oil are included in the energy - other
figures, and emissions from biofuel combustion are excluded.

The major source of carbon dioxide emissions was fossil fuel combustion (99%), with
minor emissions from lime manufacture, aluminum production, and cement production.
Carbon dioxide sinks (i.e., increases in forest carbon stocks) offset about 25% of the
total carbon dioxide emissions. Contributors to methane emissions were landfills (66%),
domesticated animals (19%), manure management (11%), coal mining (2%), and
burning of agricultural waste (1%). Nitrous oxide emissions were accounted for by
fertilizer use (97%), and the burning of agricultural waste (3%). All perfluorocarbons
were emitted from aluminum production.

Washington's emissions in 1990 were 3.5 MTCE per capita, compared to 1990 U.S.
emissions of 6.4 MTCE per capita.

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