In the Inventory, emissions and removals are categorised into six sectors:
- Agriculture (eg, livestock digestive systems, fertiliser and manure)
- Energy (eg, road transport and electricity production)
- Industrial Processes and Product Use (IPPU) (eg, production of metals and chemicals, and use of refrigerants)
- Waste (eg, landfills)
- Land Use, Land-Use Change and Forestry (LULUCF). The LULUCF sector keeps track of GHGs from land use (eg, forests, crops and pasture). This is separate from the livestock emissions reported in the Agriculture sector. It covers changes that occur in soils and vegetation from land management, and is the only sector where both emissions and removals of carbon dioxide occur.
- New Zealand’s ‘Other’ sector, Tokelau.
Gross emissions are New Zealand’s total emissions from the Agriculture, Energy, IPPU and Waste sectors, as well as gross emissions from Tokelau.
Net emissions are gross emissions combined with emissions and removals from the LULUCF sector.
Tokelau does not report LULUCF emissions, therefore gross and net emissions for Tokelau are the same in this instance.
Read the long description for New Zealand’s gross and net emissions (in million tonnes of carbon dioxide equivalent, Mt CO2-e) by sector from 1990 to 2019.
Figure 4 is a line graph that shows New Zealand’s gross and net emissions (measured in million tonnes of carbon dioxide equivalent) by sector from 1990 to 2019. Gross emissions exclude the Land Use, Land-Use Change and Forestry sector. Net emissions include the Land Use, Land-Use Change and Forestry sector. In particular, it shows:
- Gross emissions have gradually increased from 65.1 million tonnes of carbon dioxide equivalent in 1990 to 82.3 million tonnes of carbon dioxide equivalent in 2019.
- Net emissions have gradually increased from 41.1 million tonnes of carbon dioxide equivalent in 1990 to 54.9 million tonnes of carbon dioxide equivalent in 2019.
New Zealand’s gross greenhouse gas emissions were 82.3 million tonnes of carbon dioxide equivalent in 2019. This is a 2 per cent increase from 2018 emissions, primarily caused by an increase in emissions from manufacturing and construction, and public electricity and heat production, which are reported in the Energy sector.
The Agriculture and Energy sectors contributed the most to New Zealand’s emissions at 48 per cent and 42 per cent of gross emissions in 2019, respectively. Emissions from road transport made up 17.8 per cent of gross emissions.
Together, methane and nitrous oxide, largely from agricultural sources, made up over half of our gross emissions (42.1 and 10.2 per cent, respectively). The remaining emissions consisted mostly of carbon dioxide (45.5 per cent), largely from the Energy and IPPU sectors.
Since 1990, New Zealand's gross emissions have increased by 26.4 per cent. The five emission sources that contributed the most to this increase were:
- enteric fermentation due to an increase in the dairy cattle population (methane)
- fuel use in road transport (carbon dioxide)
- fuel use in manufacturing industries and construction from increased production due to economic growth (carbon dioxide)
- agricultural soils from increased fertiliser use (nitrous oxide)
- industrial and household refrigeration and air conditioning systems from increased use of hydrofluorocarbon-based refrigerants that replaced ozone depleting substances (fluorinated gases).
Net emissions include gross emissions combined with the emissions and removals from the LULUCF sector. Forests remove carbon dioxide from the atmosphere as they grow. Forests also emit carbon dioxide after being harvested, deforested, or following natural disturbances, such as storm damage. This means that historical planting rates and harvesting cycles have a large impact on the net amount of carbon dioxide removed by our forests in any given year.
To estimate net emissions, the Ministry for the Environment and the Ministry for Primary Industries calculate the area of forest in New Zealand. According to these estimates, approximately 24,067 hectares of new forest were planted and 4,745 hectares were deforested in 2019.
New Zealand’s net emissions as reported to the United Nations Framework Convention on Climate Change (UNFCCC) were 54.9 Mt CO2-e in 2019. This is calculated by subtracting the 27.4 Mt CO2-e of net removals that occurred in the LULUCF sector from gross emissions of 82.3 Mt CO2-e. Net emissions have increased by 33.5 per cent compared with 1990 levels.
Under the UNFCCC reporting rules, net emissions from the LULUCF sector offset 33 per cent of New Zealand's gross emissions in 2019. This is a decrease from 1990 when the LULUCF sector offset almost half of New Zealand’s gross emissions. This change is mainly the result of an increase in gross emissions between 1990 and 2019.
New Zealand’s gross and net emissions
© Ministry for the Environment