TABLE S.1 Current and Near-Term Capabilities for Estimating National Anthropogenic Greenhouse Gas Emissions
|
Gas
|
Major Sectors or Activities
|
Method
|
Current Uncertainty for Annual Emissionsa
|
Possible Improvements in 3-5 Years
|
Uncertainty of Improved Methods
|
|
CO2
|
Total anthropogenic
|
UNFCCC inventory
|
1 (developed countries)b
|
Adopt most accurate methods in all countries
|
1
|
|
CO2
|
Fossil-fuel combustion
|
UNFCCC inventory
|
1-2 (developed countries)
|
Adopt most accurate methods in all countries
|
1
|
|
CO2
|
Fossil-fuel combustion
|
Atmospheric measurements and models
|
4-5
|
Develop improved tracer-transport inversion through new observations (14CO2, additional ground stations, Orbiting Carbon Observatory [OCO] replacement) and data assimilation
|
1-3 (annual)
1-2 (decadal change)
|
|
CO2
|
Large local sources (e.g., cities, power plants)
|
Atmospheric measurements and models
|
5
|
Develop and deploy a CO2 satellite program, including an OCO replacement, new in situ measurements in cities, and a research program to guide network design and satellite validation
|
2 (annual)
1 (decadal change)
|
|
CO2
|
Agriculture, forestry, and other land-use (AFOLU) net emissions
|
UNFCCC inventory
|
1-4 (developed countries)
|
Adopt most accurate methods and activity data; improved emission factors through research and comprehensive ecosystem inventories
|
1-3
|
|
CO2
|
AFOLU
|
Atmospheric measurements and models
|
5
|
Develop improved tracer-transport inversion through new satellite and in situ observations
|
4-5
|
|
CO2
|
AFOLU
|
Land-use measurements and models
|
2-4
|
Develop improved observations, data assimilation, and models with ecosystem research
|
2-3
|
|
CO2
|
Deforestation and degradation source, afforestation sink
|
Land-use measurements and models
|
2-4 (forest area change)
3-4 (emissions)
|
Develop improved observations, Landsat continuity, data assimilation, and models with ecosystem research
|
1-2 (forest area change)
2 (emissions)
|
|
CH4
|
Total anthropogenic
|
UNFCCC inventory
|
2-3 (developed countries)
|
Adopt most accurate methods and activity data and improved emission factors through research
|
1-3
|
|
CH4
|
Total anthropogenic
|
Atmospheric measurements and models
|
3-5
|
Develop improved tracer-transport models, new satellite and in situ observations, and improved emission models through research
|
2-3
|
|
CH4
|
Energy, industrial processes, and waste
|
UNFCCC inventory
|
1-5 (developed countries)
|
Adopt most accurate methods and activity data and improved emission factors through research
|
1-2
|
|
CH4
|
AFOLU
|
UNFCCC inventory
|
2-4 (developed countries)
|
Adopt most accurate methods and activity data and improved emission factors through research
|
2-3
|
|
N2O
|
Total anthropogenic
|
UNFCCC inventory
|
2-5 (developed countries)
|
Adopt most accurate methods and activity data and improved emission factors through research
|
2-4
|
|
N2O
|
Total anthropogenic
|
Atmospheric measurements and models
|
4-5
|
Develop improved tracer-transport and emission models, additional observations
|
3-5
|
|
N2O
|
Energy and industrial processes
|
UNFCCC inventory
|
3-5 (developed countries)
|
Adopt most accurate methods and activity data and improved emission factors through research
|
3-4
|
|
N2O
|
AFOLU
|
UNFCCC inventory
|
2-5 (developed countries)
|
Adopt most accurate methods and activity data and improved emission factors through research
|
2-4
|
|
CFCs, PFCs, HFCs, and SF6
|
Industrial processes
|
UNFCCC inventory
|
1-4 (developed countries)
|
Adopt most accurate methods in all countries
|
1-3
|
