Long dry spell leads to less greenhouse gas

Under the Kyoto Agreement, the country has credits worth $231 million at today's carbon prices. Photo / Christine Cornege

A long, painful dry spell for farmers has helped cut the country's greenhouse gas emissions.

As farmers suffer, the latest official tally from the Ministry for the Environment reveals New Zealand is doing better than expected in the carbon stakes, partly because farms have had to cull more animals.

Because the national herd is smaller than expected the amount of greenhouse gas the country is expected to make by 2012 has fallen by 1.8 million tonnes. But that is likely to come as little comfort to farmers.

Dairy farmers north of Taupo have been cutting milk production earlier than usual, and so far rain has failed to penetrate soils in the most parched regions. In the Waikato, figures from the Ministry of Agriculture and Forestry show the drought has cost farmers an average of between $100,000 and $200,000 this year.

The Ministry said the drop in projected greenhouse gases since the last tally in 2009 was because the country had recovered more slowly than expected from a nationwide drought, and some regions had experienced another drought.

Sheep numbers fell by 5 per cent, deer numbers by 6 per cent and beef numbers were stable, while dairy numbers increased by 4 per cent, it said.

That had shaved 6.4 million tonnes of carbon dioxide equivalent (or 3.5 per cent) off expected farming emissions to 2012.

Methane and nitrous oxide from livestock make up the biggest chunk of the country's emissions, partly because the potent gases are multiplied several times when they are converted into carbon dioxide equivalents for international reporting. The next biggest source of emissions is transport.

Under the Kyoto Protocol, New Zealand has committed to pulling back the emissions it makes between 2008 and 2012 to 1990 levels or paying for the difference in carbon credits.

The latest estimates, which included the predicted effect of the emissions trading scheme, would leave New Zealand 11.4 million tonnes below 1990 levels when the four-year total is tallied, mostly because of forests sucking rising gases from other sectors.

That would leave the country with credits worth $231 million at today's carbon prices.

The position could have been better, but a re-count of forests that are eligible for carbon credits under the Kyoto protocol found fewer trees than previously thought.

Environment Minister Nick Smith warned the figures were estimates and did not necessarily reflect the Government's position, which will change when it gives out credits under the ETS.

Estimates of emissions change as methods of measuring them get better, and there are uncertainties around future changes to population, GDP and the cutting of trees that are eligible for carbon credits.

Although the drought has delivered a temporary dip, scientists working for a multimillion-dollar Government initiative are searching for less damaging ways for farmers to cut gases and still produce more milk and meat.

New types of fertiliser have already shown promise at keeping more nitrogen in the soil while saving money on nitrogen fertilisers, which can pollute streams and lakes.

The holy grail for researchers would be finding a drench or a breeding method that could cut methane belched by grass-eating farm animals.

Workers for the Pastoral Greenhouse Gas Research Consortium took a step towards this this year by mapping the genetic information of a microbe responsible for animals' emissions.

- additional reporting by James Ihaka