New Zealand vulnerable to the threats of climate change – report finds
A report released today by the Royal Society of New Zealand highlights how New Zealand will be impacted by climate
change.
It finds that climate change, already underway, will almost certainly accelerate this century unless drastic action is
taken to reduce global emissions of greenhouse gases.
It identified six areas where global climate change could have significant implications for New Zealand’s prosperity and
well-being. These are risks to:
• our coastal margins
• flooding from rivers
• availability of and competition for freshwater
• changes to our surrounding oceans
• threats to unique ecosystems
• flow-on effects from climate change impacts and responses elsewhere, which will affect New Zealand through our
strong international connectivity.
Changes expected to impact New Zealand include at least 30cm and possibly more than one metre of sea-level rise this
century – the report finds it likely that the sea level rise around New Zealand will exceed the global average, which
will cause coastal erosion and flooding, especially when combined with storm surges.
“Many New Zealanders live on the coast and two-thirds of us live in flood-prone areas so we are vulnerable to these
projected changes,” says Professor James Renwick, Chair of the Expert Panel who wrote the report.
Even small changes in average conditions can be associated with large changes in the frequency of extreme events, he
says.
“With a 30cm rise in sea level, the current ‘1 in 100 year’ extreme sea event would be expected to occur once every year
or so in many coastal regions. Along the Otago coast for example, the difference between a 2-year and 100-year storm
surge is about 32cm of sea level.”
Changes in rainfall patterns where the ‘wet gets wetter and the dry gets drier’, together with more frequent extreme
events, will put pressure on our housing, infrastructure and industry, especially if changes are rapid, the report
finds.
Freshwater resources will also likely be put under pressure, with decreasing annual average rainfall in eastern and
northern regions of both islands, plus higher temperatures and increased demand from urban expansion and agriculture.
Fire danger is also predicted to increase in many parts of New Zealand.
Changes in the oceans, including water temperature, acidification and currents will have impacts on New Zealand’s marine
life, including aquaculture. On land, existing environmental stresses to New Zealand’s unique species will likely be
exacerbated, with increased ranges for animal pests and weeds predicted.
The report also considers New Zealand’s international connections and how trade relationships and migration patterns
could change.
Royal Society of New Zealand President, Emeritus Professor Richard Bedford, says the report was sought to provide a
clear summary of the scientific evidence and projections of climate change and to identify the key risks these changes
pose to New Zealand.
“It is critical to communicate clearly New Zealand’s sensitivities to climate change and the need for responsive systems
to address them. All New Zealanders will be affected and must be involved in the discussion. We hope this report can act
as a basis for a wider national conversation.”
This report will be followed up soon by another expert panel report on how New Zealand can mitigate the impacts of
climate change.
Copies of the report and supporting resources can be found at www.royalsociety.org.nz/climatechange
Key findings – New Zealand’s sensitivities to climate change
Coastal Change: New Zealanders live mainly near coasts
Shoreline ecology, public infrastructure, residential and commercial assets, community values and the future use of
coastal-marine resources will be severely affected by changes to coasts due to sea level rise, and storm surge, and
secondary effects such as erosion and flooding.
Flooding: many New Zealanders live on floodplains
Damaging flood events will occur more often and will affect rural and urban areas differently. At and near the coast,
floods will interact with rising sea levels and storm surges. Increasing frequency and severity of high intensity
rainfall events will increase these risks.
Freshwater resources: New Zealanders rely on the availability of freshwater
Increased pressure on water resources is almost certain in future. Decreasing annual average rainfall in eastern and
northern regions of both main islands, plus higher temperatures, are projected to increase the frequency and intensity
of droughts and the risk of wild fire. At the same time, urban expansion and increased demand for water from agriculture
will result in increased competition for freshwater resources.
The Ocean: New Zealand is surrounded by sea
Changes in ocean temperature, chemistry, and currents due to climate change will have impacts on New Zealand’s marine
life, fishing, aquaculture and recreation use.
Ecosystem change: New Zealand has unique ecosystems
Over half of New Zealand’s more than 50,000 species are found nowhere else in the world; over three quarters of the
vascular plants, raising to 93% for alpine plants, and over 80% for the more than 20,000 invertebrates. Existing
environmental stresses will interact with, and in many cases be exacerbated by, shifts in mean climatic conditions and
associated change in the frequency or intensity of extreme events, especially fire, drought, and floods.
International Impacts: New Zealand is affected by impacts and responses to climate change occurring overseas
The ways in which other countries are affected by and will respond to climate change, plus commitments New Zealand makes
to international climate treaties, will influence New Zealand’s international trade relationships, migration patterns
and specific domestic responses.
Report launch
The launch for the findings of this expert panel is at 11am on Tuesday 19 April at the Royal Society of New Zealand in
Thorndon, Wellington. It will feature special international guest Professor Jean Palutikof, Director of the National Climate Change Adaptation Research Facility at Griffith University, Queensland. Professor
Palutikof previously managed the production of the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment
Report for Working Group II (Impacts, Adaptation and Vulnerability). Professor Palutikof will give a public talk in
Wellington that evening.
Climate Change Implications for New Zealand Panel Members
Professor James Renwick (Chair): Physical Geography Professor, Victoria University, Wellington
Dr Barbara Anderson: Rutherford Discovery Fellow, Landcare Research Manaaki Whenua, Dunedin
Dr Alison Greenaway: Social Researcher, Landcare Research Manaaki Whenua, Auckland
Darren King: Environmental Scientist, National Institute of Water and Atmospheric Research (NIWA), Wellington
Dr Sara Mikaloff-Fletcher: Atmosphere-Ocean Scientist, National Institute of Water and Atmospheric Research (NIWA), Wellington
Dr Andy Reisinger: Deputy Director (International), New Zealand Agricultural Greenhouse Gas Research Centre, Wellington
Dr Helen Rouse: Resource Management Scientist, National Institute of Water and Atmospheric Research (NIWA), Christchurch
ENDS