ISSUE #6: Environment

KPI: Human GHG Emissions (Million Tonnes CO₂-e)

AKA: climate change, pollution

The environment consists broadly of air/space, waters, land/plants, animals, and climate, however, the KPI that is most spoken about is human GHG emissions.
The Covid limitation and lockdown rules that began on 19 March 2020 nationwide and the final lockdown that ended on 15 December 2021 in Auckland, including international travel, obviously had a significant impact on emissions for some of this timeframe. Context and judgments like this are subjective, so they are impossible to show in a graph. It is up to each reader to evaluate the proportion of responsibility they place on each government over the timeframe shown, versus factors outside of their control.
Remember that each Labour-led or National-led government has had coalition partners that share the successes, and the failures, with them. A full list of governments for this time range is at the bottom of this page.

Data shown:

Totals of million tonnes carbon dioxide equivalent (C02-e) in a year. See ‘Why this KPI?’ below for more details.
Human gross GHG emissions
Human net GHG emissions

1990 onwards as that is when New Zealand’s Greenhouse Gas Inventory began, and up to 2021 being the last year that report was produced since there is a 1.3-year delay.

Data not shown:

Stats NZ’s 2022 gross emissions estimate, since we want to compare data from the same data set, and also gross vs. net.

Full data:

Frequency:

Updated:

Last update:

Next update:

The most commonly referenced environmental statistic is human greenhouse gas emissions, or GHG for short.
The correct technical term is anthropogenic emissions (human-induced), which means/isolates the changes humans have made in their surrounding environment.
GHG is measured in million tonnes carbon dioxide equivalent (C02-e) by creating a combined metric of various greenhouse gases:
- CO2 = Carbon Dioxide (approximately 45% of NZ’s anthropogenic GHGs)
- CH4 = Methane (~43%)
- N2O = Nitrous oxide (~10%)
- Combined F-gases (~2%)
The Ministry for the Environment measures both:
- Gross emissions.
- Net emissions after new carbon sequestration activities in that time period, e.g. planting trees.
Because the political policies by both of the main parties reference 2030 targets in nominal terms, and also the net zero goal by 2050, we show absolute nominal numbers too, and not emissions per capita or as a % of GDP. However, these are also very useful KPIs that we will share as resources allow.
It’s important to note that this measurement is contested. Some argue the science, some question the accounting, and others believe that New Zealand’s natural sequestration of carbon from all plant life, e.g. grasses, seaweed, mangroves, and plankton too, exceeds the additional emissions from New Zealanders each year.

Temperatures

Earth’s temperatures over history have risen and fallen with different ages, e.g. the ice age, and the extinction of the dinosaurs, and major volcanic events, so this is a very difficult and contested measurement, and not a great one for the environment KPI.

With support, we’ll be able to add multiple KPIs for each issue:

Updates on many of KPIs listed above.
Landfill per capita
True recycling (not just what is collected)
Air quality/pollution
Lake/river/ocean quality
Drinking water quality (coming on www.theFacts.nz soon)
Renewable electricity generation
Rainfall over history
Temperatures over history
Trees (can be misleading if the pastures replaced aren’t counted, or native plantings aren’t counted)

1987 = Labour
1990 = National
1993 = National*
1996 = National/NZ First*
1999 = Labour/Alliance + Green
2002 = Labour/Progressive + United
2005 = Labour/Progressive + United, NZ First
2008 = National + ACT, United, Māori
2011 = National + ACT, United, Māori
2014 = National + ACT, United, Māori
2017 = Labour/NZ First + Green
2020 = Labour + Green

Sources:1,2 (table 5).

Data published by Ministry for the Environment
© Crown Copyright
Licensed for use under the creative commons attribution licence (BY) 4.0

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