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3 Assigned amount units

The projected volume of assigned amount units for New Zealand is calculated from actual emissions reported in the most recent national inventory of greenhouse gas emissions and removals (MfE 2006 in press). The number of assigned amount units is equal to five times the emissions reported for New Zealand's base year of 1990. In the 2006 submission of the inventory for 2004, the emissions in 1990 were 61.5 million tonnes carbon dioxide equivalent (rounded to one decimal place). Each emissions unit is equal to one tonne of greenhouse gas emissions, converted to carbon dioxide equivalents using the global warming potential for each greenhouse gas (IPCC Second Assessment Report 1995). This equates to 307.6 million assigned amount units (rounded to one decimal place) over the first commitment period.

The projected volume of assigned amount units has not changed noticeably since the 2005 estimate despite the effect of recalculations in the national inventory. Recalculations are improvements in data, emission factors or methodologies that are back-dated from the current inventory to 1990. Recalculations are a recognised aspect of the Intergovernmental Panel on Climate Change's good practice guidance for inventory preparation.

New Zealand's 2004 national inventory of greenhouse gas emissions and removals was submitted to the United Nations Framework Convention on Climate Change on 13 April 2006 and is currently undergoing publication (MfE 2006 in press). Under the rules of the Kyoto Protocol, the inventory submitted with the Kyoto Protocol initial report will set the final volume for the assigned amount. New Zealand is exercising its option of resubmitting an inventory with its initial report on 1 September 2006. In future net position reports, the assigned amount will be the value set out in the upcoming initial report. Therefore, the value reported here may be subject to change.

3.1 National trends in New Zealand's emissions

In 1990, New Zealand's total greenhouse gas emissions (excluding the land use, land-use change and forestry sector) were equivalent to 61.5 million tonnes carbon dioxide. In 2004, total greenhouse gas emissions were equivalent to 74.6 million tonnes carbon dioxide. This equates to a 13.1 million tonnes carbon dioxide equivalent (21.2 percent) [In the national greenhouse gas inventory total emissions are sometimes reported as increasing by 21.3 percent. This is due to small quantities of emissions (approximately 0.08 Mt CO2-e) of nitrous oxide and methane in the land use land-use change and forestry sector being included in total emissions and calculated as total emissions by gas rather than total emissions by sector.] rise in greenhouse gas emissions since 1990 (Chart 2) from the five sources of emissions shown in Table 2.

The decrease in emissions from 2003 to 2004 visible in Chart 2 is due to emissions in 2003 growing exceptionally fast due to low rainfall and an increased reliance on fossil fuel thermal generation. There was less fossil fuel thermal generation required and consequently less emissions from energy generation in 2004.

Chart 2: New Zealand's total greenhouse gas emissions 1990-2004, excluding the land use, land-use change and forestry sector (Million tonnes carbon dioxide equivalent)

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There have been changes in the relative amounts of the different greenhouse gases emitted since 1990. Whereas methane and carbon dioxide contributed equally to New Zealand's emissions in 1990, carbon dioxide is now the major greenhouse gas in New Zealand's emissions profile. This is caused by higher growth in the energy sector compared to the agriculture sector.

New Zealand is unusual amongst developed nations with a large proportion (49.4 percent) of emissions total emissions in 2004 being produced by the agriculture sector (Chart 3). By comparison, emissions from agriculture typically make up 12 percent of total greenhouse gas emissions across Annex I Parties. The agricultural emissions are predominantly methane emissions from ruminant farm animals, and nitrous oxide emissions from animal excreta and nitrogenous fertiliser use. The current level of emissions from the agriculture sector is 4.8 million tonnes carbon dioxide equivalent (14.8 percent) above the 1990 level (Table 2).

The energy sector is the other large component of New Zealand's emissions profile, comprising 42.4 percent of total emissions in 2004. Emissions from the energy sector are now 8.0 million tonnes carbon dioxide equivalent (33.8 percent) above the 1990 level (Table 2). The growth in energy emissions since 1990 is primarily from road transport (an increase of 4.9 million tonnes carbon dioxide equivalent or 62.7 percent) and electricity generation (an increase of 2.6 million tonnes carbon dioxide equivalent or 73.6 percent). Emissions from fossil fuel thermal electricity generation vary from year to year depending on the water resources available for hydro generation. In 'dry' years there is a greater reliance on thermal electricity generation.

Emissions from the industrial processes and waste sectors are a much smaller component of New Zealand's emissions profile, comprising 5.6 percent and 2.5 percent respectively of all greenhouse gas emissions in 2004. Emissions from the waste sector are now 25.9 percent below the 1990 baseline with the majority of the reduction occurring from improvements in management of solid waste disposal. New Zealand's relatively small manufacturing base means that solvent use is lower than in many other countries.

Chart 3: New Zealand's sectoral emissions in 2004

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Table 2: Annual sectoral emissions of greenhouse gases in 1990 and 2004 (Million tonnes carbon dioxide equivalent)

Sector

 

Change from 1990

Change from 1990 (percent)

 

1990

2004

2004

2004

Energy

23.7

31.6

8.0

33.8

Industrial processes

3.2

4.2

1.0

30.7

Solvent and other product use

0.0

0.0

0.0

16.4

Agriculture

32.1

36.9

4.8

14.8

Waste

2.5

1.8

-0.6

-25.9

Total emissions

61.5

74.6

13.1

21.2

Source: Ministry for the Environment (2006 in press)

Note: One emissions unit is equivalent to one tonne of greenhouse gas emissions converted to carbon dioxide equivalents by the global warming potential.

Note: Total excludes small emissions of nitrous oxide and methane from the land use, land-use change and forestry sector.