

		Ministry of Agriculture and Forestry Te Manatu Ahuwhenua, Ngaherehere

Issue 10 June 2002

From the Editor

This RM Update issue is focused on the topical issue of climate change. The Government has recently announced its preferred policy package for reducing greenhouse gas emissions in response to climate change and the Kyoto Protocol. Instead of focussing on the policy debate this RM Update issue examines some of the technical issues involved with agriculture and greenhouse gases and aims to provide information on greenhouse gas emissions from agriculture, regional impacts and adaptation strategies, the effects of climate change on water supply, mitigation options, and the possibility of using bio-ethanol for transport fuels.

Duane Redward, Editor

In this Issue:

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Greenhouse Gas Emissions From New Zealand Agriculture

Agriculture has received considerable attention regarding its contribution to New Zealand's greenhouse gas emissions. The following article by Gerald Rys presents information on the agricultural contribution to greenhouse gas emissions in New Zealand. Introduction The world is warming and the climate is changing. This is the conclusion of the Intergovernmental Panel on Climate Change (IPCC) in its latest Third Assessment Report (2001). Climate change is considered one of the most serious threats to the sustainability of the world's environment, human health and well-being, and the global economy. Mainstream scientists agree that the Earth's climate is being affected by the build-up of greenhouse gases (GHGs), such as carbon dioxide, caused by human activities. A majority of scientists believe that precautionary and prompt action is necessary. The effects of climate change are already measurable and include:

the world's 10 warmest years have all been since 1983 - seven of them since 1990;
the global mean temperature went up about 0.6°C between 1861 and 2000;
sea levels rose between 10 to 20 cm between 1900 and 2000;
glaciers are retreating;
Arctic sea ice is thinning and reducing;
1998 was the world's - and New Zealand's - hottest year since records began.

The graphs below clearly illustrate the increasing global temperature pattern.

Figure 1: Variations in surface temperature for the last 1000 years and projected temperature rise under the range of IPCC future scenarios

Source: IPCC Third Assessment Report One; Climate Change: The Scientific Basis, 2001

New Zealand’s Emissions Profile

New Zealand is required to submit an annual inventory to the United Nations Framework Convention on Climate Change. The inventory presented for 2001 gave the following GHG emission and sink levels in carbon dioxide equivalents (Table 1).

Table 1: Emissions and removals of greenhouse gases in New Zealand in 1990 and 1999 as reported in New Zealand’s National Inventory Report 2001. All data is in thousands of tonnes of CO2 equivalents.

	CO2	CO2	CH4	N2O	HFCs	PFCs	SF6	Total
	Emissions	Removals						Emissions
1990	25,399	-22,307	35,211	11,849	Negligible	603	2.87	73,065
1999	30,523	-23,245	33,594	12,397	210	74	33.2	76,831

Note the significant increases in carbon dioxide emissions over the nine-year period are due largely to increases in transport and energy emission increases. Recent reviews of the methodology used for establishing emissions from agriculture suggest that there is an increase (rather than decrease) in methane emissions (above 1990 levels) and that current nitrous oxide emissions (above 1990 levels) are greater than currently identified. These changes have yet to be peer reviewed and incorporated into the national inventory. The reasons for these differences are discussed later. Table 2 presents the distribution of GHGs between different sectors in 1990 and 1999. The dominance of the agriculture sector is clearly evident. The agricultural sector emissions are made up largely of methane and nitrous oxide and have significant uncertainties associated with them. This means New Zealand has one of the highest uncertainties in its national inventory compared with other developed countries party to the Kyoto Protocol. These high uncertainties mean New Zealand needs to ensure that we carry out research and establish best practice methods for deriving our agricultural inventory.

Table 2: Gross relative radiative forcing (% in CO2 equivalents) - relative sectoral shares in 1990 and 1999 (National Communication, Ministry for the Environment, 2001)

Sector	1990	1999
Energy	33	38
Processes	4	4
Agriculture	59	54
Waste	4	4

Future Developments in the National Inventory

Establishing the current quantity of emissions from agriculture at a national level is not a trivial exercise. While standard values can be adopted through the IPCC Good Practice Guidelines, these values do not reflect the unique circumstances of New Zealand agriculture. New Zealand is seeking to adopt a more comprehensive national approach to assessing our GHG emissions from agriculture. The government approved additional funds this year to improve the national agricultural inventory. This has enabled a detailed re-valuation of the basis for calculating national emissions. The research results have identified some interesting factors that will change the basis of past, present and future calculations. These factors include incorporating assessment of changing animal performance, New Zealand-specific methane emission and nitrogen input factors. One key question that the animal science community can address is the extent to which changes in animal performance, over time, are the result of more efficient feed conversion or better and/or more forage intake, and the relationship of these to methane output. The table below shows MAF figures on changes in some livestock performance attributes over the last 10 years. These changes are clearly due to past research and its adoption by farmers, and are a tribute to the success of past agricultural research in New Zealand.

Table 3: Livestock performance in New Zealand (1990 to 2000).

Product	Season Ended	1990	1991	1992	1993	1994	1995	1996	1997	1998	1999	2000
Wool/Sheep	30 June	5.1	5.3	5.4	4.9	5.7	5.8	5.5	5.8	5.7	5.5	5.6
(kg Greasy)
Lambing %	30 June	96.6	100.4	105.7	95.4	102.5	107.3	104.3	111.9	117.3	113.6	114.9
Graded Lamb	30 Sept.	13.8	14.1	14.3	15.1	15.2	14.6	15.2	15.9	15.4	15.7	16.7
(kg/carcass)
Graded Beef	30 Sept.	237	240	233	248	250	244	242	254	241	240	245
(kg carcass)
Milksolids/Cow	31 May	232	233	254	252	275	255	259	283	280	262	300
(kg)

Conclusions

Deriving a New Zealand Agricultural GHG National Inventory is a difficult and complex task. There are uncertainties in many of the parameters used to derive the inventory. This also means that any means of reducing GHG emissions in agriculture will have a significant impact on the national inventory. A programme of research has been instigated to ensure New Zealand will be using "best- practice" methods in deriving our national agricultural emissions in the future. This is important to ensure New Zealand meets international review panel requirements of our obligations under the Kyoto Protocol. Current research suggests that New Zealand agriculture will be significantly over the 1990 baseline GHG emissions by 2010; the middle of the first commitment period to the Kyoto Protocol. This is largely due to increasing animal performance since 1990 and the change in the balance of the numbers of different animal species e.g. decreased sheep and increased dairy animal numbers.

Gerald Rys
Senior Policy Analyst, Sustainable Resource Use Group, MAF Policy

Gerald has a background in agricultural science and science policy. He gained his agricultural science degree from Massey and his PhD for the University College of Wales. He was a scientist with MAF for 15 years carrying out largely agronomic research in Taranaki, Palmerston North and Hawkes Bay before moving to the Ministry of Research, Science and Technology. He recently moved back to MAF to take up a position in the sustainable resource use group looking at climate change and water issues.

Contact for Enquiries

Amber Duncalfe
Editor - RM Update
Ministry of Agriculture and Forestry
PO Box 2526
Wellington
NEW ZEALAND

Tel: +64 4 894 0710
Fax: +64 4 894 0745
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