Deluges and disasters will strike N. Zealand more often*

Saturday March 31, 2007
By Angela Gregory

New Zealand will increasingly be hit by heavy rainfall causing flooding,
landslides and erosion, says a draft report into the effects of future
climate change.

The Weekend Herald was yesterday told some of the key findings in the
report of the Intergovernmental Panel on Climate Change (IPCC) affecting
New Zealand.

Entitled "Impacts, Adaptation, and Vulnerability", the report is due for
release after finalisation in Brussels next week.

It predicts significantly increased rainfall in most of New Zealand -
except for the east of the North Island and the north of the South
Island - and consequences such as landslides.

The report predicts warming of 0.2C to 1.3C by the 2030s, and from 0.5C
to 3.5C by the 2080s.

It says New Zealand is already experiencing impacts from recent climate
change and noted the 2004 North Island floods cost about US$78 million
($109 million).

It used the Bay of Plenty as a case study to show that while beachfront
properties there demanded the highest premiums on the property market,
they faced the highest risks of future flooding, storm surge and erosion
in the region.

Aileen Lawrie, coastal planner for Environment Bay of Plenty, was not
surprised, saying the regional council had already identified 1000
coastal properties at risk from those hazards within a 100-year timeframe.

When property owners planned to replace existing structures, they were
being encouraged to build relocatable dwellings, and the council was not
allowing future development in high-risk coastal areas.

The IPCC report said it had "high confidence" in its scientific findings
of stresses on agriculture and changes to natural ecosystems in response
to climate change.

It forecast reduced seasonal snow cover and shrinking glaciers. New
Zealand's snow line was likely to rise by 120m to 270m based on
scenarios for the 2080s.

Changes in seasonal snow cover were likely to have a significant impact
on the ski industry, but that could be partly offset by increased
tourist flows from Australia given relatively poor snow conditions there.

Shrinking glaciers would mean fewer visitors to West Coast towns.

Mike Smith, marketing manager of Ruapehu Alpine Lifts, said there was
already evidence of rising snow lines but still a lot of volatility in
seasonal snowfalls.

Mr Smith said snow-making technology and management was keeping ahead of
climatic shifts. "A snow line rise of 200m would mean very little."

The IPCC indicated both positive and negative impacts of climate change
on forestry.

Growth rates for plantation forests were likely to increase in the south
and west of the country.

However, a reduction in tree growth was predicted for the eastern North
Island from rainfall decreases, and the warmer and drier weather could
increase the frequency of upper mid-crown yellowing and winter fungal
diseases.

The kiwifruit industry would suffer delayed bud break and reduced
yields. In Northland, the production of current varieties was likely to
be uneconomical by 2050 because of a lack of winter chilling.

Dave Kelly, a Kerikeri kiwifruit grower, said substantial breeding
programmes were underway.

"I'd be surprised if we were growing the same varieties in 40 years ...
we will adapt."