The Government has set what is says is an achievable, fair target for cutting atmosphere-warming emissions, but critics say the new target is "100 per cent pure spin" and a paltry increase on past commitments.
All countries are expected to set new targets for reducing greenhouse gas emissions before crucial climate change talks in Paris in December, which will establish a road map for the period after 2020.
Minister for Climate Change Issues Tim Groser confirmed yesterday New Zealand's target would be to reduce greenhouse gas emissions by 30 per cent from 2005 levels by 2030.
He described it as a "significant increase" on the 2020 target, which was a reduction of 5 per cent below 1990 levels. If the new target was set to a 1990 baseline, it was the equivalent of an 11 per cent reduction.
Labour and the Greens slammed the target, saying the Government should match the European Union by setting a target of at least a 40 per cent reduction on 1990 levels.
Green Party spokesman Kennedy Graham said using 2005 as a benchmark was "pure spin". Once the usual benchmark of 1990 was considered, the reduction was paltry, he said.
Mr Groser said the 2005 benchmark aligned with big players such as the US and Canada. In a consultation paper, the Ministry for the Environment estimated raising the target from 5 per cent to 10 per cent would cost households $30 more a year. Raising it to 40 per cent would cost households about $530 a year.
But environmental advocates said the ministry had failed to include the cost of not acting on climate change. A 2013 drought fuelled in part by man-made climate change, for example, cost the New Zealand economy more than $1.3 billion.
Mr Groser said there were fewer opportunities for New Zealand to immediately reduce its emissions because about half its pollution came from producing food "for which there aren't yet cost-effective technologies to reduce emissions".
In 2013, New Zealand produced 400 tonnes of CO2 equivalent per unit of GDP. Of this total, 48 per cent came from agriculture and 22 per cent from transport.
Youth climate change organisation Generation Zero said 69 per cent of 15,000 submitters had wanted a target of 40 per cent or higher.
5% reduction on 1990 levels
2030: 11% reduction on 1990 levels (or 30% reduction on 2005 levels)
2050: 50% reduction on 1990 levels