Table 1.5.3 Key category analysis for the 2003 inventory - Tier 1 trend assessment

Tier 1 Source Category Trend Assessment
IPCC source categories	Gas	Base year estimate Gg	2003 estimate Gg	Trend assessment	Contribution to trend	Cumulative total
Including LULUCF activities
Mobile combustion - road vehicles	CO₂	7534.65	12094.67	0.031	16.9	16.9
Emissions from enteric fermentation in domestic livestock	CH₄	21530.77	23592.21	0.030	16.3	33.2
Forest land remaining forest land	CO₂	22677.47	25583.91	0.024	12.9	46.1
Emissions from stationary combustion - solid	CO₂	3169.41	5435.29	0.017	9.2	55.3
Direct emissions from agricultural soils	N₂O	585.22	2185.55	0.016	8.7	63.9
Emissions from solid waste disposal sites	CH₄	2177.70	1425.48	0.013	7.3	71.3
Emissions from stationary combustion - gas	CO₂	7682.58	8558.10	0.009	5.0	76.3
Emissions from agricultural soils - animal production	N₂O	6767.81	7454.62	0.009	4.9	81.2
Conversion to forest land	CO₂	960.59	1765.49	0.006	3.5	84.6
PFCs from aluminium production	PFC	515.60	80.70	0.006	3.2	87.9
Emissions from substitutes for ozone depleting substances	HFCs	0.00	403.96	0.004	2.4	90.3
Emissions from stationary combustion - liquid	CO₂	2546.55	2797.95	0.003	1.9	92.2
Mobile combustion - aviation	CO₂	772.83	1158.33	0.002	1.2	93.4
Fugitive emissions from geothermal operations	CO₂	357.34	269.11	0.002	1.0	94.4
Emissions from manure management	CH₄	574.51	549.44	0.002	0.9	95.3
Additional key categories when excluding LULUCF activities
Mobile combustion - road vehicles	CH₄	148.20	50.44	0.002	0.9	95.5