New Zealand's greenhouse gas emissions – published February 2022
What is measured
This indicator measures New Zealand’s greenhouse gas (GHG) emissions in carbon dioxide equivalent (CO2-e) units from 1990 to 2019, using data from New Zealand’s Greenhouse Gas Inventory 1990-2019.
Why it is important
Climate change is primarily caused by the accumulation of GHGs in the atmosphere due to human activities. GHGs absorb heat from Earth’s surface, warming the atmosphere. Different GHGs remain in the atmosphere for different amounts of time, ranging from a few years to thousands of years. Emissions of gases with a long lifetime (more than a few decades) build up in the atmosphere, with this year’s emissions added on to previous decades and even centuries of emissions. For short-lived gases, their contribution to global warming depends mainly on their current rate of emission. Regardless of their lifetime, every emission of every gas contributes to global warming.
New Zealand’s share of global GHG emissions is small, but our gross emissions per person are high. New Zealand has several domestic and international greenhouse gas emissions reduction targets (see Greenhouse gas emissions targets and reporting).
Key findings
New Zealand’s gross greenhouse gas (GHG) emissions have shown no obvious sustained reductions compared with 2005. In 2019 New Zealand’s gross greenhouse gas emissions were 82.3 million tonnes of CO2-e, 0.2 percent lower than 2005 and 26.4 percent higher than 1990. Emissions were 2.2 percent higher than 2018.
In 2019:
Gross GHG emissions were mainly made up of carbon dioxide (45.5 percent), methane (42.1 percent), and nitrous oxide (10.2 percent).
Carbon dioxide emissions were mainly produced by transport (42.9 percent), manufacturing industries and construction (20.0 percent), and public electricity and heat production (11.1 percent).
GHG emissions from transport were up 84.8 percent from 1990 and up 16.6 percent from 2005. They were down 0.1 percent from 2018. Transport emissions in 2019 were mainly made up of road vehicle emissions (90.5 percent) and domestic aviation (6.3 percent).
GHG emissions from manufacturing industries and construction were up 59.7 percent from 1990 and up 51.8 percent from 2005. They were up 11.0 percent from 2018. They made up 20.0 percent of all carbon dioxide emissions in 2019.
GHG emissions from public electricity and heat production were up 19.4 percent from 1990 and down 53.3 percent from 2005. They were up 20.8 percent from 2018. A high proportion of electricity generation in New Zealand is from renewable sources. In 2020, the share of electricity generated from renewable energy sources in New Zealand was 81.1 percent (Ministry of Business, Innovation & Employment, 2021).
Gross methane emissions were mainly produced by livestock (88.4 percent). Methane emissions from livestock in 2019 were up 9.0 percent from 1990 and down 1.6 percent from 2005. They were up 0.3 percent from 2018. Livestock methane emissions in 2019 were mainly produced by cattle digestion (65.1 percent) and sheep digestion (27.9 percent).
Gross nitrous oxide emissions mostly came from agricultural soils (92.8 percent), at least half (50.2 percent) of which was from urine and dung deposited by grazing animals. Overall, nitrous oxide emissions were up 45.3 percent from 1990 and up 5.9 percent from 2005. They were up 0.4 percent from 2018. Nitrous oxide made up 19.9 percent of all agriculture emissions in 2019.
Fluorinated gases contributed only 2.2 percent to gross greenhouse gas emissions, but their emissions have been growing rapidly. While 2019 emissions from fluorinated gases were 4.6 percent lower than 2018, they were 97.7 percent higher than 1990, and 133.1 percent higher than 2005.
Our net greenhouse gas emissions were 54.9 million tonnes, 33.5 percent higher than 1990 due to the underlying increase in gross emissions, and 4.0 percent lower than 2005. The total amount of greenhouse gas emissions removed by forest land in New Zealand ranged between 21.1 million and 36.8 million tonnes over the period 1990 to 2019. In 2019 net GHG emissions were 2.0 percent higher than 2018.
Where this data comes from
Ministry for the Environment
View data tables
You can also download data from the visualisation tool on this page. However, the data from the tool does not contain metadata, and does not have the same name as the data tables.
Related indicators
Global greenhouse gas emissions
Related content
Our atmosphere and climate 2020
Our atmosphere and climate 2017
New Zealand’s Greenhouse Gas Inventory
New Zealand’s Interactive Emissions Tracker
New Zealand’s greenhouse gas emissions reduction targets
United Nations Framework Convention on Climate Change
About the data
We obtained emissions data from New Zealand’s greenhouse gas inventory, which is produced by the Ministry for the Environment (MfE) as part of New Zealand’s reporting obligation under the United Nations Framework Convention on Climate Change and the Kyoto Protocol (Ministry for the Environment, 2021).
The GHG inventory groups emissions and removals into six sectors according to the process that generates the emissions:
- agriculture (for example, livestock digestive systems and manure)
- energy (for example, road transport and electricity production)
- industrial processes and product use (IPPU) (for example, production of metals and chemicals, and use of refrigerants)
- waste (for example, landfills)
- land use, land-use change and forestry (LULUCF): the LULUCF sector keeps track of greenhouse gases from land use (for example, for forests, crops, and pasture). This is separate from the livestock emissions reported in the agriculture sector. It covers our use of soil, trees, plants, biomass, and timber and is the only sector where carbon dioxide is removed from the atmosphere.
- estimated greenhouse gas emissions from Tokelau (a dependent territory of New Zealand) are included as a separate sector.
Gross emissions are the total emissions from Tokelau, and the agriculture, energy, IPPU and waste sectors. Net emissions are gross emissions combined with emissions and removals from the LULUCF sector. In 2019 Tokelau contributed 0.005 percent to New Zealand’s gross greenhouse gas emissions.
Inventory estimates are recalculated every year, from the base year (1990) to the latest year. This means the emissions estimates are only up to date in the latest GHG inventory, and previous inventories are not useful for comparisons. Changes made to the inventory are often related to improvements in activity data collection, emission factors, and methodology, or the identification of additional emission sources.
The inventory reports on four GHGs (or, in the case of fluorinated gases, groups of GHGs) because of their ability to absorb heat and their relatively long residence in the atmosphere.
- Carbon dioxide (CO2) is added to the atmosphere primarily through the combustion of fossil fuels (coal, oil, and gas), and from some chemical reactions, such as the production of cement. Once emitted, a fraction of it can remain in the atmosphere for thousands of years (Archer et al., 2009). It is removed from the atmosphere primarily through biomass production from photosynthesis and dissolution in the oceans.
- Methane (CH4) is emitted by livestock and the decomposition of organic matter (such as in landfills) as well as during the production and transportation of coal and natural gas. Over a span of 100 years it is 25 times more effective than CO2 at trapping heat, despite its average lifetime in the atmosphere of about 12 years.
- Nitrous oxide (N2O) is emitted primarily from agriculture, but also industrial processes and fossil fuel combustion. Over a span of 100 years it is 298 times more effective than carbon dioxide at trapping heat, and has an average atmospheric lifetime of 114 years.
- Fluorinated gases (F-gases) cover hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulphur hexafluoride (SF6). These are very strong human-made GHGs used in products such as refrigerators and air conditioners. Emissions to the atmosphere come during production and through losses during product use. Their average lifetimes in the atmosphere vary from days to 50,000 years.
We report greenhouse gas (GHG) emissions in carbon dioxide equivalent (CO2-e) units, which is a measure for comparing greenhouse gases based on their heating effect over a period of time, compared to that of an equivalent amount of carbon dioxide as the reference. CO2-e is used for describing different greenhouse gases in a common unit, which allows them to be reported consistently.
The Intergovernmental Panel on Climate Change (IPCC, 2021) defines the ‘global warming potential’ (GWP) as ‘An index measuring the radiative forcing following an emission of a unit mass of a given substance, accumulated over a chosen time horizon, relative to that of the reference substance, carbon dioxide (CO2). The GWP thus represents the combined effect of the differing times these substances remain in the atmosphere and their effectiveness in causing radiative forcing.’
For this indicator, GHG global warming potentials, with a time horizon of 100 years, are obtained from the Intergovernmental Panel on Climate Change Fourth Assessment Report (IPCC, 2007), consistent with the guidelines set out by the United Nations Framework Convention on Climate Change for current emissions reporting (updated values are available from the IPCC).
However, GWP is not the only way of comparing gases, and a range of metrics has been developed to compare the effect on climate from the emission of different gases. Different metrics focus on different aspects of climate change, which can result in different weighting for gases with different lifetimes. All metrics have uncertainties and limitations, and equivalence of emissions with regard to one aspect of climate change does not imply equivalence with regard to any other aspect (IPCC, 2021).
We display IPCC ranges directly against relevant emissions from New Zealand. New Zealand’s emissions reductions targets (not shown) are in part based on the IPCC special report on 1.5 degrees but may differ from those shown.
Note that the IPCC’s Summary for Policymakers – Global warming of 1.5 °C provides estimates of the global reductions of agricultural methane, agricultural nitrous oxide, and net carbon dioxide by 2030 and 2050 relative to 2010 in modelled scenarios that limit climate change to 1.5°C above pre-industrial levels with no or limited overshoot (see p14). We have displayed these global benchmarks in the relevant graph as vertical lines representing the interquartile (central) range of reductions across the modelled emissions pathways to provide context and aid the interpretation of current levels of New Zealand greenhouse gases. These ranges represent global least cost reductions to achieve the 1.5°C limit. They do not represent national targets for New Zealand (not shown). Setting national targets requires a thorough investigation of a country’s individual circumstances and its share of the global burden.
The data used in this analysis is not the same as that used to show New Zealand’s contribution to global GHG emissions, which was produced using the World Resources Institute’s Climate Analysis Indicators Tool (CAIT) data from the Climate Watch online platform.
Data quality
The accuracy of the data source is of high quality.
New Zealand’s greenhouse gas emissions is a direct measure of the ‘Human activities generating greenhouse gases’ topic.
Stats NZ and the Ministry for the Environment must report on topics related to the five environmental domains: air, atmosphere and climate, fresh water, land, and marine. These topics identify key issues within each domain.
Topics for environmental reporting describes the topics for each domain.
Data quality information has more information about the criteria we use to assess data quality.
References
Archer, D., Eby, M., Brovkin, V., Ridgwell, A., Cao, L., Mikolajewicz, U., … Tokos, K. (2009). Atmospheric Lifetime of Fossil Fuel Carbon Dioxide. Annual Review of Earth and Planetary Sciences, 37(1), 117–134. https://doi.org/10.1146/annurev.earth.031208.100206
Intergovernmental Panel on Climate Change. (2021). Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change (V. Masson-Delmotte, P. Zhai, A. Pirani, S. L. Connors, C. Péan, S. Berger, N. Caud, Y. Chen, L. Goldfarb, M. I. Gomis, M. Huang, K. Leitzell, E. Lonnoy, J. B. R. Matthews, T. K. Maycock, T. Waterfield, O. Yelekçi, R. Yu, & B. Zhou, Eds.). Cambridge University Press. https://www.ipcc.ch/report/ar6/wg1/
Intergovernmental Panel on Climate Change. (2007). Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, 2007 (S. Solomon, D. Qin, M. Manning, Z. Chen, M. Marquis, K. B. Averyt, M. Tignor, & H. L. Miller, Eds.). Cambridge University Press. https://www.ipcc.ch/report/ar4/wg1/
Ministry for the Environment. (2021). New Zealand’s greenhouse gas inventory 1990–2019. https://environment.govt.nz/publications/new-zealands-greenhouse-gas-inventory-1990-2019/
Ministry of Business, Innovation and Employment. (2021). Energy in New Zealand 2021. https://www.mbie.govt.nz/building-and-energy/energy-and-natural-resources/energy-statistics-and-modelling/energy-publications-and-technical-papers/energy-in-new-zealand/
Archived pages
Archived February 2022:
New Zealand’s greenhouse gas emissions – published October 2020
