Northland is likely to be hit by more droughts and wildfires in the coming decades as rainfall drops and temperatures rise, according to the UN's latest update on climate change.
Released yesterday, the nearly 2000-page Intergovernmental Panel on Climate Change update brings together scientists' findings since the last report in 2007 and tries to predict climate changes by 2100. It points to a continued trend of higher temperatures in New Zealand and lower rainfall in the north and east of the North Island. The west is expected to get wetter.
As a result droughts are expected to become more frequent in Northland. More fires are likely as well as longer fire bans in summer. The Far North is already the country's busiest fire district. Its current restricted fire season was declared in the October, the earliest on record.
Coastal regions such as Northland may also have to contend with infrastructure damage, flooding and erosion caused by rising sea levels. In the worst case sea levels will rise by just under a metre (0.53-0.97m) by 2100 but with tough mitigation the rise could be 0.28-0.6m.
While the report makes grim reading for Australia, New Zealand can expect some benefits from climate change. They include reduced need for heating in winter and hence lower energy demand, and fewer deaths from winter illnesses. Forestry and crops may benefit as plants grow faster in higher temperatures and CO2 levels.
The panel also examined countries' preparedness for climate change and concluded New Zealand had a significant ''adaptation deficit''. The country was already witnessing climate change in the form of extreme weather events, the report stated.
Climate Change Minister Tim Groser welcomed the report and said it re-emphasised the importance of adapting to climate change, but others have criticised what they see as Government inaction.
Victoria University's Tim Naish, a lead author for the previous report, said the update strengthened the case for anthropogenic climate change. Extreme weather events would become more frequent as wet areas in the west of the country received more rain and dry areas such as the Far North and East Cape became drier. That would have implications for water resources, agriculture and horticulture.
''This report is a wake-up call for New Zealand to take its head out of the sand, to take a longer-term view - at least longer than an electoral cycle - and rise to the challenge of adaptation if we are to future-proof this country for coming generations,'' Dr Naish said.
Northland-based Green MP David Clendon said the country had to reduce its emissions of greenhouse gases and do what it could to adapt. An obvious way for Northland to cut emissions would be to shift freight from roads to rail and coastal shipping; the region could also make itself less vulnerable to storms by using more localised solar and geothermal power generation, reducing the number of people affected when power lines were brought down.
Better land use and planning rules would reduce the impact of flooding but could require tough decisions such as relocating coastal properties, Mr Clendon said.
More research was needed on alternative crops and farming systems. Dairying was carbon-intensive and required a lot of water, which the report predicted would come under increasing pressure in Northland.
The monster report has 309 authors from 70 countries, supported by 436 contributors and 1729 experts and reviewers. It was released in Yokohama, Japan, on Monday.