Rising tempetatures are putting New Zealand's agricultural industry and coastal communities at increasing risk, according to a new UN draft report that warns resulting problems will continue to grow.
The fifth Intergovernmental Panel on Climate Change report, due to be released tomorrow, shows that on top of those concerns, New Zealand is not doing enough to prepare for them.
The draft chapter on Australasia seen by the Sunday Star-Times has also warned of increased risk of bushfires, the potential extinction of native species such as the tuatara, and a dearth of information on how to adapt to the potential impact.
The report said it was virtually certain warming would continue throughout the 21st century, resulting in rising snow lines, increased rainfall risk in some areas and drought in others, with average rainfall decreasing in the north-east of the South Island and northern and eastern North Island.
Sea levels could rise by up to 110cm - meaning current high-tide levels would become low-tide marks and lead to further inundation of coastal sites.
It said that, without adaptation, further changes in climate, CO 2 levels and ocean acidity are projected to have a substantial impact on water resources, coastal ecosytems, infrastructure, health, agriculture and biodiversity.
On the flip side, electricity demands would reduce in winter due to less need for heating, and spring pasture growth in cooler regions would increase and be beneficial to agriculture.
Dr James Renwick, an Associate Professor at Victoria University's School of Geography, Environment and Earth Sciences said this report was the second of three - following an initial report he contributed to, which looked at temperatures - and was focused on the impact.
The latest report was consistent with what had been highlighted previously - generally that wet areas would get wetter and dry areas drier.
In New Zealand, the west coast and south-west would get more water overall and the north and east less.
"So the kind of drought we're experiencing in the north of the North Island at the moment - we're likely to see more of those in the future."
The draft report said average global sea levels would rise by up to 0.97m by 2100 but were likely to be 10 per cent higher in most of New Zealand, where the tidal range is about one metre.
"We're talking about what is now the high-tide line becoming the low-tide line and the beach will still go inland," Renwick said, adding the increased risk to coastal areas was "a big deal".
An average warming of 2 degrees was a certainty "and we could be looking at 4 degrees by the end of the century, and who knows what beyond that. That would mean big changes for natural ecosystems, big changes for agriculture, big changes all round".
This would see more extreme heat and less extreme cold which would have varying effects on New Zealand's primary industries - fewer frosty mornings, which would affect pipfruit for example, though the report says temperature changes could boost forestry production.
"It would really interfere with agricultural systems and it would allow lots of pest species that can't live in New Zealand to survive here quite happily," Renwick said.
The draft report pointed to the fact that drought in New Zealand cost about $3.6b in direct and off-farm output between 2007-2009 and said the 2012-2013 drought was expected to have reduced GDP by 0.3 to 0.6 per cent and contributed to a rise in global dairy prices. Aquaculture and fisheries could also be affected.
Another criticism in the report was the lack of direction from central government. Changes were driven largely at a local level and were constrained by a lack of information and limited financial and human resources.
While the capacity to adapt here was high "there are formidable environmental, economic, informational, social, attitudinal and political constraints, especially for local governments and small or highly fragmented industries".
Professor Gary Wilson from the NZ Antarctic Research Institute said New Zealand was not doing enough to prepare for inevitable changes because we did not know enough about what we should be preparing for.
The country was hugely dependent on its weather and environment-based industries, and the challenge was to think further ahead. For example, farmers needed to think less about short-term profitability and more about whether or not the farm would remain viable for future generations, he said.
But he did not expect the report to have a major impact, as he was yet to see any political appetite to address the issues.
"We're highly responsive to an earthquake - that's in our face - but with a problem that's much more insidious like climate change, it's easy to go home at night and get up each day and say ‘it hasn't changed' and we just tend to ignore it - but at our children's peril," he said.
Green Party co-leader Russel Norman said the report was "a big wake-up call". "Unfortunately, because the Government are climate deniers they're just not doing anything to get us prepared for it."
More direction from central government was needed to empower local councils to introduce measures to cope.
He pointed to the Kapiti Coast District Council's attempt to introduce coastal hazard zones which were blocked through legal action by affected residents.
Federated Farmers chief executive Connor English said extreme weather was more on farmers' minds than ever before but they were adaptable and were changing their practices accordingly.
Climate change minister Tim Groser declined to comment.
- Sunday Star Times
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