Measuring, reporting and accounting for our emissions

Information on the three types of emissions data we report on and its purposes.

Emissions types

There are three types of emission data.

  • Gross emissions (UNFCCC reporting). Emissions from all sectors of the New Zealand economy, excluding forestry and land-use emissions/removals.
  • Net emissions (UNFCCC reporting). Emissions from all sectors of the New Zealand economy, including all forestry and land-use emissions/removals.
  • Target accounting emissions. This is what we use to measure progress towards our target. Target accounting emissions include all of our gross emissions, but only a subset of our forestry and land-use emissions. The subset used for our 2030 target is a modified version of those used for our 2012 and 2020 targets. This will ensure incentives for new forest planting remain but the cyclical emissions from planting and harvesting in our plantation forests is removed. These rules ensure our approach has credibility and integrity. More detail is on the NDC Registry website.

Our targets also set out the level of reduction in greenhouse gas emissions New Zealand is contributing towards international action on climate change.

UNFCCC reporting and target accounting

We report our emissions for two different purposes:

  • to compile an inventory of all of our domestic emissions and removals which we submit annually to the UNFCCC
  • to show progress towards our targets.

For showing progress towards our targets, we use the accounting guidelines of the relevant target period. The objectives of the accounting guidelines are to ensure our targets are only being judged against factors we have control over. For example the growth, harvest and re-planting cycle of plantation forests that already existed prior to 1990 are excluded from accounting for our target, unless they are permanently cut down.


Forestry and other land-use emissions are included in New Zealand’s national greenhouse gas inventory under a category called ‘land use, land-use change and forestry’ (LULUCF). While under the LULUCF category we report on the changes in carbon stored in all of our land area, most of the impact from LULUCF in New Zealand is due to forests.

Accounting for forestry is complex because:

  • trees can both remove carbon dioxide from the atmosphere (as they grow) and then emit this to the atmosphere again (as/if they are cut down)
  • there are different rules for forests which existed before 1990 compared to those established after 1989. This distinction was created in the international accounting rules of the Kyoto Protocol (which apply until 2020). We will use a modified version of the Kyoto rules for accounting for forestry towards our Paris target. The detailed explanation is on the NDC Registry website.

Carbon budgets

New Zealand uses a multi-year ‘carbon budget’ approach to setting and measuring progress towards our targets. This means progress towards our target is not measured by looking at emissions in a single year (for example 2012, 2020 or 2030) but includes a comparison of emissions in all the years of each target period (2008–12, 2013–20 and 2021–30). This approach was required by countries that took a target under the Kyoto Protocol and has been used by New Zealand for all subsequent targets as well.

Gross-net accounting

Accounting for New Zealand’s targets (and those of other developed country signatories to the Kyoto Protocol) is often described as ‘gross-net accounting’. This is because the carbon budget is calculated in relation to historic gross emissions but  then compared to our target accounting emissions.

Using this approach ensures measuring progress towards our target only considers those factors that we have control over. If our national targets were mistakenly assessed using net emissions from our UNFCCC reporting, our targets would appear much less ambitious than they actually are because net emissions for UNFCCC reporting are much lower than the target accounting emissions.