Climate change itself is complicated, and the language used to talk about it is no different.

We've put together a guide to help explain some of the words and phrases around climate change, from greenhouse gases and carbon offsetting, to the Paris Agreement.

A breakdown of the language

Carbon emissions

When we talk about carbon emissions, we're focusing on emissions of carbon dioxide, or CO2. Carbon dioxide emissions are the main driver of global warming and climate change.

Carbon footprint

A carbon footprint is the total amount of greenhouse gases created by the activities of an individual, business, or community. For example, an individual's carbon footprint is increased if they drive a petrol-fuelled vehicle, heat their houses with gas or coal or eat red meat. You can measure and track your carbon footprint using tools like FutureFit(external link).

Carbon neutral

To be carbon neutral, the emissions of an activity (like flying) are offset by other activities that reduce emissions (e.g. planting native forest). The end result is that there is no increase in the atmospheric concentration of gases that cause global warming.

Carbon offsetting

Carbon offsetting compensates for greenhouse gas emissions from industrial or other human activities, by making equivalent reductions of greenhouse gas in the atmosphere.

Examples of carbon offsetting include investment in projects that reduce or store carbon, like forest preservation and tree planting.

Carbon sequestration

Scientists are investigating technologies that store carbon dioxide away from the atmosphere such as pumping it underground to store or 'sequester' it. The goal is to keep the carbon dioxide away from the atmosphere to reduce its warming effect.

However, many experts don't see carbon sequestration as a solution as the technology still isn't proven at scale, and we need to take immediate action to reduce greenhouse gas emissions.

Carbon zero

Carbon zero means that an activity has no emissions that impact on the atmosphere and increase global warming. There are different definitions of carbon zero and the term is often used interchangeably with carbon neutral.

Climate change

Climate change is the change in global or regional climate patterns which started becoming increasingly visible in the mid-to-late 20th century. The changes are the result of global warming caused by the increased levels of atmospheric greenhouse gases produced by burning fossil fuels.

We're now in a period of rapid climate change. Long-term effects of these changes include how much rain falls in a region or changes to the usual temperature, as well as rising sea levels. The world is about 1.2°C warmer than before people started using oil, gas and coal to power factories and transport, and to heat homes.

Scientists have recommended a maximum temperature increase of 1.5°C as the "safe" limit for global warming.

COP26

COP stands for 'Conference of the Parties', referring to the countries that have signed up to the 1992 United Nations Framework Convention on Climate Change. The next meeting – COP26 – will be held in Glasgow on 31 October – 12 November 2021. New Zealand is a party to COP and will be represented at this meeting.

Emissions trading scheme (ETS)

New Zealand's emissions trading scheme puts a price on carbon emissions. The Government requires entities that are responsible for greenhouse gas emissions to surrender one emissions trading scheme unit for each tonne of carbon dioxide equivalent they emit. The surrender obligation is generally placed on larger organisations, like fuel suppliers and power generators.

The number of units available to the market is limited, meaning that over time, the cost of units is expected to increase, putting pressure on entities to reduce their emissions.

Global warming

Global warming is the rapid increase in Earth's average surface temperature over the past century, mainly caused by increased levels of greenhouse gases that prevent heat from leaving the earth's atmosphere. Most of this greenhouse gas increase is caused by people burning fossil fuels.

The world is about 1.2°C warmer than before people started using oil, gas and coal to power factories and transport, and to heat homes.

Scientists have recommended a maximum temperature increase of 1.5°C as the "safe" limit for global warming.

Greenhouse gases

Greenhouse gases prevent heat from leaving the atmosphere. The natural level of greenhouse gases keeps the earth warm enough to be inhabitable but increases from the natural level lead to global warming and climate change. Greenhouse gases include carbon dioxide or CO2 (increases in CO2 are largely from burning fossil fuels), chlorofluorocarbons, water vapor, methane, and nitrous oxide.

We create greenhouse gas emissions when we burn fossil fuels – driving a petrol car or diesel truck, catching a plane, as well as burning gas or coal for heat. About 40% of New Zealand's emissions are from energy use.

Gross and net emissions

Gross emissions are New Zealand's total emissions from the Agriculture, Energy, Industrial Processes and Product Use (IPPU), and Waste sectors, as well as gross emissions from Tokelau.

Net emissions are New Zealand's gross emissions combined with emissions and removals from the Land Use, Land-Use Change and Forestry (LULUCF) sector. Historically, our LULUCF sector has removed emissions from the atmosphere.

Kyoto Protocol

The Kyoto Protocol is an international treaty that extended the 1992 United Nations Framework Convention on Climate Change and committed signatories to reduce greenhouse gas emissions. The protocol is based on the scientific consensus that global warming is occurring and that human-made  CO2 emissions are driving it. New Zealand is one of 192 countries that signed up to the protocol. The Kyoto Protocol finished in 2021 and was replaced by the Paris Agreement.

Paris Agreement

The Paris Agreement is a legally binding international treaty on climate change. It was adopted by 195 countries at a meeting in Paris in 2015 attended by countries that had signed up to the United Nations Framework Convention on Climate Change.

At the meeting, the concept of handling climate change and its impacts was approved by virtually every nation. The agreement intends to reduce global greenhouse gas emissions and limit the increase in global temperatures to below 2 degrees Celsius.

New Zealand's current commitment is to reduce greenhouse gas emissions by 30 percent below 2005 levels by 2030.

Production and consumption emissions

New Zealand measures emissions in two ways: production-based methodology, and consumption-based methodology.

  • Production-based emissions are the emissions from goods that are produced in New Zealand and either consumed in New Zealand or overseas.
  • Consumption-based emissions are the emissions associated with the production of goods that are consumed in New Zealand – these include locally produced or imported goods, but not goods exported from New Zealand.

Zero Carbon Act

The Climate Change Response (Zero Carbon) Amendment Act 2019 provides a framework that lets New Zealand develop and implement clear and stable climate change policies. The changes do four key things:

  • set a new domestic greenhouse gas emissions reduction target for New Zealand
  • establish a system of emissions budgets to act as stepping stones towards the long-term target
  • require the Government to develop and implement policies for climate change adaptation and mitigation
  • establish the Climate Change Commission.