As they develop their economies, Pacific Island nations must plan for the impacts of climate change within most of their sectors, such as infrastructure, says NIWA's Pacific Rim Manager, Doug Ramsay.
"Infrastructure is one particular sector where incorporating climate change considerations is critical because of the long life spans of developments such as roads," says Doug. He and his NIWA team have been working with the Government of the Republic of Kiribati in the central Pacific, to develop climate-related design information to assist with land-use planning and infrastructure decision-making.
They also developed spread sheet based tools to enable Government staff to access and apply climate information as they plan for more resilient infrastructure such as roads, coastal defences, causeways, and stormwater drainage.
The tools were recently used to help design coastal protection for assets on South Tarawa, and to help set minimum ground levels for a new residential development at the eastern end of the atoll.
Kiribati – a cluster of 32 atolls and one raised coral island – is one of the most vulnerable island nations. Much of the main atoll, Tarawa, is barely half a kilometre wide, and lies just three metres above sea level. South Tarawa's high population density, socio-economic conditions, along with the limited land area and low-lying land levels, leave it particularly susceptible to the impacts of coastal flooding and climate change.
South Tarawa consists of many smaller islets, linked by narrow causeways which can be overtopped when large waves combine with high sea levels.
Doug says there are a number of approaches that can be adopted to incorporate climate change considerations into island infrastructure such as these causeways. However, given the current uncertainty over the magnitude of future sea level rise (anything between 50 centimetres to a metre or more by the end of this century) an adaptive management approach may be most effective – staging adaptation activities over time in response to improved climate and sea level rise projections.
Making appropriate decisions demands good information, says Doug, from both historical climate records and future projections. His team compiled both to give the Kiribati Government the best possible foundation for future development.
"But," he says, "getting access to good quality data can be a significant challenge – particularly when you're looking at extreme conditions; you need at least 30 years of good data to derive some of those extremes."
"The tools will be adapted to help with development work elsewhere in the Pacific" says Doug. "We're adapting some of the tools we developed in Kiribati to assess how climate change may impact on coastal flooding and the implications for land-use planning in the Cook Islands.
See the NIWA Year in Review 2011 for more stories about our work.