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 under way, will almost certainly accelerate this century unless drastic action is taken to reduce global emissions of greenhouse gases.
It identifies 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.
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.
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
Professor Jean Palutikof, director of the National Climate Change Adaptation Research Facility at Griffith University, Queensland, was a special guest at the launch at the Royal Society premises in Thorndon, Wellington, this morning.
Professor Palutikof previously managed the production of the Intergovernmental Panel on Climate Change Fourth Assessment Report for Working Group II (Impacts, Adaptation and Vulnerability).
He will give a public talk in Wellington tonight.