Climate change science and the international context
Climate change science
Climate change is defined as "a change of climate that is attributed directly or indirectly to human activity that alters the composition of the global atmosphere and that is in addition to natural climate variability observed over comparable time periods" (Article 1, United Nations Framework Convention on Climate Change [UNFCCC]).
Our climate has undergone many changes over the last million years. While natural changes in climate have been gradual, over the last 50 years the Earth 's atmosphere has been heating up at an unprecedented rate, an effect known as global warming. Since this warming also affects global weather patterns and climatic conditions, it is more accurately referred to as "climate change".
Modern human activity (such as global industrialisation, agriculture and transportation) is increasing the amount of greenhouse gases being released into our atmosphere.
The main greenhouse gases released by human activity are carbon dioxide (CO2), methane, nitrous oxide and some synthetic industrial gases. In New Zealand, 49.2% of greenhouse gas emissions are produced by the agriculture sector (methane and nitrous oxide) and 42.8% from the energy sector (CO2).
Emissions from the industrial processes and waste sectors are a much smaller component of New Zealand's inventory comprising 4.7% and 3.2% respectively.
More information on climate change science and associated international initiatives can be found at the NZ Climate Change website.
United Nations Framework Convention on Climate Change (UNFCCC)
The United Nations Framework Convention on Climate Change (UNFCCC) was adopted by the United Nations at the "Earth Summit" in Rio de Janeiro in May 1992. The UNFCCC took effect on 21 March 1994.
The long-term objective of the UNFCCC is to prevent "dangerous anthropogenic (man-made) interference with the climate system". The Convention sets out broad principles for change and has set up a process for governments to meet regularly. It encourages scientific research, sharing and exchange of technology and know-how, education about the effects of climate change and how we can deal with them.
The 189 countries that have ratified the UNFCCC (including New Zealand) have legally committed to taking measures to address climate change, including greenhouse gas inventories, national or regional programmes, and preparation for adaptation to the impacts of climate change. More information on the UNFCCC can be found at the NZ Climate Change website or at the UNFCCC website.
Intergovernmental Panel on Climate Change
The World Meteorological Organisation and the United Nations Environment Programme established the Intergovernmental Panel on Climate Change (IPCC) in 1988. The IPCC's role is to assess what we know about the climate system, the impacts of climate change and possible ways forward. It does not carry out research or monitor climate-related data or other relevant parameters (refer to the IPCC website for further information).
In response to the First Assessment Report of the IPCC, the United Nations' General Assembly convened a series of meetings that culminated in the adoption of the UNFCCC.
The Kyoto Protocol
The Kyoto Protocol, which New Zealand ratified in 2002, is an international agreement to address global warming and delay climate change. It came into effect on 16 February 2005. It aims to reduce the total greenhouse gas emissions of developed countries (and countries with economies in transition) to 5% below the level they were in 1990. An extension of the UNFCCC, the Kyoto Protocol sets targets for the greenhouse gas emissions of developed countries for the period 2008 to 2012 (the first commitment period). Different countries have to achieve different targets. New Zealand's target is to reduce its greenhouse gas emissions to the level they were in 1990, or take responsibility for excess emissions. More information on the Kyoto Protocol can be found at the NZ Climate Change website.
