New Zealand's Greenhouse Gas Inventory

New Zealand's Greenhouse Gas Inventory is produced each year as part of Aotearoa New Zealand’s obligations under the Paris Agreement and United Nations Framework Convention on Climate Change (UNFCCC).

The Inventory is the official annual report of all human-induced emissions and removals of greenhouse gases in Aotearoa. It is the key source of evidence on Aotearoa New Zealand’s greenhouse gas emissions trends.

Aotearoa New Zealand’s Inventory data are used for both international and domestic reporting. It informs Aotearoa New Zealand’s policy recommendations on climate change and enables us to monitor progress towards our emissions reductions targets.

The Inventory is a Tier 1 statistic under Aotearoa New Zealand's Official Statistics System. This means it is one of the most important publicly available statistics for understanding how well Aotearoa is performing.

Tier 1 statistics [Stats NZ website]

Previous Inventories

Previous inventory submissions since 2003.

The Ministry for the Environment compiles and submits the inventory to the UNFCCC. Usually this happens by April 15.

This year is the first year of reporting under the Paris Agreement. Because of this, we will submit the Inventory to the UNFCCC later this year. However we published the inventory on our website in April.

We work closely with the Ministry of Business, Innovation and Employment, the Ministry for Primary Industries and the Government of Tokelau’s Ministry of Climate, Oceans and Resilience. Many of the values used in the inventory are derived from data collated by Stats NZ.

The inventory reports greenhouse gas emissions and removals from five sectors:

• Agriculture
• Energy
• Industrial Processes and Product Use (IPPU)
• Land Use, Land-Use Change and Forestry (LULUCF)
• Waste

Tokelau’s emissions are also reported separately by sector as ‘Other’.

Gross emissions are Aotearoa New Zealand's total emissions from Agriculture, Energy, IPPU and Waste sectors as well as gross emissions from Tokelau.

Net emissions are made up of gross emissions combined with emissions and removals from the LULUCF sector.

The LULUCF sector keeps track of greenhouse gases from land use (eg, 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.

The most recent inventory report published in April 2024 covers greenhouse gases which have direct warming effects:

• carbon dioxide (CO₂)
• methane (CH₄)
• nitrous oxide (N₂O)
• hydrofluorocarbons (HFCs)
• perfluorocarbons (PFCs)
• sulphur hexafluoride (SF₆)
• nitrogen trifluoride (NF₃).

Only emissions and removals of these direct greenhouse gases are included in the national greenhouse gas total.

The inventory also reports indirect greenhouse gases but they are not included in Aotearoa New Zealand’s greenhouse gas total. These gases do not have a direct warming effect, but react with other gases in the atmosphere and increase the concentration of direct greenhouse gases.

The indirect gases are:

• oxides of nitrogen (NOx)
• sulphur dioxide (SO₂)
• carbon monoxide (CO)
• non-methane volatile organic compounds (NMVOCs).

International reporting guidelines govern what the inventory covers and when it is submitted. The inventory year is 15 months behind the current calendar year to give countries time to collect and process the inventory data and prepare the submission. The latest inventory, published in April 2024 contains data from 1990 to 2022 inclusively. All Annex I countries report using the same international guidelines.

For List of Annex 1 countries [UNFCCC website].

Aotearoa New Zealand's inventory is compiled using internationally agreed guidelines produced by the Intergovernmental Panel on Climate Change (IPCC).

2006 IPCC Guidelines for National Greenhouse Gas Inventories [IPCC website]

Aotearoa New Zealand's inventory is reviewed annually by a team of international experts certified by the UNFCCC. Review reports are published up to 15 months after submission of the inventory.

See the latest review report on Aotearoa New Zealand’s inventory [UNFCCC website].

When the methodology or underlying data change, the whole inventory time series from the base year to the latest year is recalculated. This means that the emissions estimates are only up to date in the latest 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.