New Zealand can and must do more to fight climate change on the home front, say authors of a high-level report out today.
In the second of two major papers published by the Royal Society of New Zealand, researchers have laid out a range of actions they say the country could start taking now.
An initial report, issued last week, warned several degrees of temperature increase by the end of century would put the country further at risk of flooding, drought, storm surge and put even greater pressure on waterways and ecosystems.
A follow-up being launched in Wellington today provides a blueprint for shifting to a low-carbon economy through improvements in energy, transport, building, agriculture, industry and land use.
Massey University sustainable energy expert Professor Ralph Sims, who led the panel of authors, said there were already many options that were well understood, achievable and likely to have flow-on benefits.
"Business-as-usual approaches will not get us where we need to be; ambitious action is needed now by all New Zealanders."
The report noted how the impact of New Zealand's Emissions Trading Scheme - used to meet our emissions target through buying carbon credits from a range of overseas sources - had been limited in reducing actual domestic emissions.
Around half of New Zealand's greenhouse gas emissions stem from burning coal, oil and gas for electricity, transport, industry heat processes and other everyday uses, with the rest coming from agriculture through emissions of nitrous oxide from animal waste and methane, mainly belched from ruminant cattle.
Ways to improve transport, still 99 per cent dependent on fossil fuels, included setting vehicle fuel efficiency standards, encouraging the use of low or zero-emissions vehicles and prioritising walking, cycling and public transport in urban design.
Considerable emissions savings could be made by moving road freight to shipping or rail, Professor Sims said. "As an example, the transport of one tonne of freight by diesel-powered rail produces less than a third of the emissions than transport over the same journey by road."
Professor Sims thought it was possible to reach - and even surpass - New Zealand's goal to be generating 90 per cent of its electricity from renewable sources by 2025.
This would require a more flexible grid that would incorporate small-scale, renewable electricity generation systems, along with energy storage and back-up generation.
Buildings could be retrofitted to improve energy balance, hungry appliances could be replaced, codes and standards could be strengthened and the use of fossil fuels for industrial heat supply could be reduced by greater uptake of solar thermal, geothermal and biomass resources.
Planting new forests was one practical method to remove large volumes of carbon dioxide from the atmosphere in the short- to medium-term.
Making a big dent in agricultural emissions would be challenging unless the country reduced its reliance on animal protein production.
Smarter farming practices, selectively breeding stock and adjusting rumen biology to reduce emissions would help.
Climate Change Minister Paula Bennett said the report would be a "useful resource as we transition to a low-emissions economy".
"I hope it sparks more innovation and discussion on how we can achieve this. I want to hear from all sectors on how we move forward."
Labour climate spokeswoman Megan Woods said the report showed our present pathway was "inadequate".
"It's time for the Government to ditch its old-fashioned approaches ... and move into the 21st century."
Greens co-leader James Shaw said top scientists had already pointed out that delaying action isn't an option.
"The report shows the Government will fail to cut emissions if it relies on finding a technological silver bullet," he said. "The Government should be investing for the future in a high-value, clean-tech, jobs-rich economy rather than in sunset industries like offshore oil and gas."