The annual inventory of emissions and removals of greenhouse gases (the inventory) forms part of New Zealand’s obligations under the United Nations Framework Convention on Climate Change (the Climate Change Convention) and the Kyoto Protocol. The inventory also forms an element of the Ministry for the Environment’s state of the environment reporting.
The inventory reports the emissions and removals of greenhouse gases not controlled by the Montreal Protocol. The gases include carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs) and sulphur hexafluoride (SF6). The indirect greenhouse gases – carbon monoxide (CO), oxides of nitrogen (NOx), sulphur dioxide (SO2) and non-methane volatile organic compounds (NMVOCs) – are also reported in the inventory. Under the Climate Change Convention, only emissions and removals of the direct greenhouse gases (CO2, CH4, N2O, HFCs, PFCs and SF6) are reported in the national greenhouse gas total. The gases are reported under six sectors: energy, industrial processes, solvent and other product use, agriculture, land use, land-use change and forestry (LULUCF), and waste.
Only human-induced emissions and removals of greenhouse gases are reported in the inventory. This submission in 2009 includes a complete time series of emissions and removals from 1990 through to 2007 (the current inventory year). Each inventory report is 15 months in arrears allowing time for data to be collected and analysed.
Primarily, the inventory fulfils reporting obligations under the Climate Change Convention. Through the first commitment period of the Kyoto Protocol, supplementary information needs to be included in the inventory. In this inventory submission, New Zealand has reported supplementary information under the Kyoto Protocol in Annex 8. This includes information on transactions of Kyoto Protocol units during the 2008 calendar year.
National trends in New Zealand’s emissions and removals
In 1990, New Zealand’s total greenhouse gas emissions were 61,852.8 Gg CO2 equivalent (CO2-e). In 2007, total greenhouse gas emissions were 75,550.2 Gg CO2-e equating to a 13,697.4 Gg CO2-e (22.1 per cent) rise in emissions since 1990 (Figure 1.1). Net removals of CO2 through forest sinks increased from 18,138.5 Gg CO2 in 1990 to 23,836.0 Gg CO2 in 2007.
Between 2006 and 2007 emissions decreased 2,048.9 Gg CO2-e (2.6 per cent). This was due to two major factors. The first was a drought throughout the summer and autumn of 2007/2008. The drought affected many regions, leading to reduced livestock numbers and productivity. The reduction in livestock population, especially in sheep and deer, led to a 679.8 Gg CO2-e (2.7 per cent) decrease in CH4 emissions. Decreases in livestock productivity led to a 381.4 Gg CO2-e (3.0 per cent) decrease in N2O emissions.
The second factor was the commissioning of Genesis Energy’s combined cycle gas turbine at Huntly and the corresponding reduction in coal-fired electricity generation. This led to a decrease in emissions in the public electricity and heat production subcategory of 1,449.5 Gg CO2-e (17.9 per cent) between 2006 and 2007.
The predominant greenhouse gases emitted by New Zealand have changed since 1990. Whereas CH4 and CO2 contributed equally to New Zealand’s emissions in 1990, in 2007 CO2 was the major greenhouse gas in New Zealand’s emissions profile (Table 1.1). This growth in emissions of CO2 reflects the growth in emissions from the energy sector compared to the agriculture sector.
Table 1.1 New Zealand’s emissions of greenhouse gases in 1990 and 2007
|Greenhouse gas emissions||Gg CO2-equivalent||Change from 1990 (Gg CO2-equivalent)||Change from 1990 (%)|
|CO2 (excluding LULUCF)||25,337.6||35,231.5||9,893.9||39.0|
|CH4 (excluding LULUCF)||25,428.5||26,560.1||1,131.6||4.5|
|N2O (excluding LULUCF)||10,429.3||12,845.6||2,416.3||23.2|
Note: The per cent change for hydrofluorocarbons is not applicable (NA) as there was no production of hydrofluorocarbons in 1990.
Source and sink category emission estimates and trends
New Zealand’s emissions profile is unique amongst developed nations. In 2007, 36,430.0 Gg CO2-e (48.2 per cent) of total emissions were produced by the agriculture sector (Figure 1.2). By comparison, emissions from agriculture are typically 11 per cent of total emissions for developed nations or Parties listed in Annex I of the Climate Change Convention. New Zealand’s agricultural emissions are predominantly CH4 emissions from ruminant farm animals and N2O emissions from animal excreta and nitrogenous fertiliser use. In 2007, emissions from the agriculture sector were 3,918.9 Gg CO2-e (12.1 per cent) above the 1990 level of 32,511.1 Gg CO2-e (Table 1.2 and Figure 1.3).
The energy sector is the other large component of New Zealand’s emissions profile, comprising 32,653.1 Gg CO2-e (43.2 per cent) of total emissions in 2007. Emissions from the energy sector were 9,200.3 Gg CO2-e (39.2 per cent) above the 1990 level of 23,452.8 Gg CO2-e (Table 1.2 and Figure 1.3). The growth in energy emissions since 1990 has primarily been from the road transport subcategory (an increase of 5,832.9 Gg CO2-e or 76.2 per cent) and the public electricity and heat production subcategory (an increase of 3,167.9 Gg CO2-e or 91.3 per cent). Emissions from thermal electricity generation vary from year to year depending on the water resources available for hydro generation, as in dry years there is a greater reliance on thermal electricity generation.
Emissions from the industrial processes and waste sectors are a small component of New Zealand’s emissions profile, comprising 6.1 per cent and 2.4 per cent respectively of all greenhouse gas emissions in 2007. Due to improvements in solid waste disposal, emissions from the waste sector decreased 616.4 Gg CO2-e (25.3 per cent) since 1990. Emissions from industrial processes increased 1,192.7 Gg CO2-e (35.0 per cent) since 1990. Emissions from the solvent and other product use sector are negligible in New Zealand.
The land use, land-use change and forestry (LULUCF) sector represents a major carbon sink for New Zealand, sequestering 23,836.0 Gg CO2-e in 2007. Net removals increased 5,697.5 Gg CO2-e (31.4 per cent) from the 1990 level of 18,138.5 Gg CO2-e. Variations in planting rates of forestry and the impact of harvest regimes affect the size of this carbon sink from year to year.
The LULUCF sector of the inventory is not the same as forest sinks or afforestation under the Kyoto Protocol. The inventory reports emissions and removals from all forests (planted and natural) for all years, whereas under the Kyoto Protocol only new planting and any deforestation after 31 December 1989, enters the accounting system.
Note: The Industrial processes emissions shown here, includes emissions from the solvent and other product-use sector.
|Solvent and other product||43.4|
|Land-use change and forestry||-23,836.0|
|Solvents and other product use||41.5||43.4|
Table 1.2 New Zealand’s sectoral emissions of greenhouse gases in 1990 and 2007
|Sector||Gg CO2-equivalent||Change from 1990 (Gg CO2-equivalent)||Change from 1990 (%)|
|Solvent and other product use||41.5||43.4||1.9||4.6|
|Total (excluding LULUCF)||61,852.8||75,550.2||13,697.4||22.1|
|LULUCF (including CH4 & N2O)||–18,138.5||–23,836.0||–5,697.5||31.4|
|Net Total (including LULUCF)||43,714.3||51,714.2||7,999.9||18.3|