Natural Hazards Update - No.19 July 2008

Kiribati – adapting to the challenges of climate change

 

Tarawa coastline. (Photo: Doug Ramsay, NIWA)

 

NIWA has a long relationship with many Pacific Island nations, where natural hazards pose numerous threats to life and livelihoods. We are involved in many projects to reduce climate and coastal hazard-related risks to Pacific states. NIWA’s Doug Ramsay and Scott Stephens have recently been in Tarawa, the capital of the Republic of Kiribati, contributing to the Kiribati Adaptation Programme (KAP) – the Kiribati Government’s initiative to plan for the effects of climate change.

NIWA’s role in the KAP includes assessing hazards such as drought, high intensity rainfall, extreme sea levels and wave conditions, and how these hazards may change with changing climatic conditions over the next 100 years.

We held workshops and briefings to update Government officials and others on our present understanding of global climate change, climate change projections, and most importantly, the implications for Kiribati. Doug and Scott also trained Government staff to apply climate coastal information using software tools developed for the project. For example Kiribati has been experiencing drought over much of the past year due to the prolonged La Niña. Workshop participants were able to calculate that, up to the end of February, such a drought would occur once every 4.5 years on average.

Kiribati – the next 100 years:

• Temperature: projected to increase by between 1.2 0C and 5.6 0C.
• Rainfall: both average and high intensity rainfall are likely to increase over all islands. A 1-in-50 year 24-hour high intensity rainfall event could become a 1-in-20 year event.
• Tides: a present-day king tide level in Tarawa could be exceeded by more than 75% of all high tides by the end of the century. The majority of Kiribati’s 105 000 population live in Tarawa, only three metres above sea level.
• Drought: the number of droughts per decade is likely to remain about the same.

Meet us at Te Papa at the 2^nd Australasian Natural Hazards Conference

Many of NIWA’s natural hazards staff will be at the 2nd Australasian Natural Hazards Management Conference at Te Papa, Wellington, 28–31 July 2008.

We will be demonstrating EcoConnect, our real-time environmental forecasting service, and talking about our work to increase understanding of how community involvement can influence coastal hazard management outcomes. With GNS Science, we will also be demonstrating RiskScape, our regional risk modelling tool.

NIWA’s Rob Bell and Stefan Reese are facilitating two of the eleven workshops: Planning for climate change impacts on coastal hazards, and Forecasting and modelling wind hazards.

Further information at: www.hazards-education.org/ahmc/2008/2008index.php

We look forward to seeing you there!

Tsunamis in the Futuna archipelago – what risk?

   

Piecing together the history of tsunamis in the Futuna archipelago is a new challenge for NIWA scientists..

The archipelago is on the North Fijian Transform Fault – one of the most active fault zones in the world. Futuna itself is a tiny island with 4000 inhabitants living almost exclusively on coastal land.

Tectonic activity in the past has created steep underwater slopes capable of generating large submarine landslides. These are potential generators of tsunamis. So, the risk of a tsunami is high, but what we don’t know is when, and how often, tsunamis have occurred in the past.

Our work in Futuna will include:

• A land-based survey of evidence of past tsunamis, including radio-carbon dating of sediments. We can then try to link past tsunamis with known past volcanic or seismic events, and estimate their recurrence interval.
• A study of the undersea environment of the archipelago to identify the origin of local historic tsunamis. Using multibeam bathymetry (maps of seafloor contours), we can analyse evidence of past landslides and then develop numerical models of tsunamis.

Ultimately the work will help establish realistic scenarios of why and how tsunamis could occur in future, and the level of risk to people living in the archipelago.

The project is funded by the Pacific Fund of the French Ministry of Foreign Affairs and will be run jointly between NIWA and the Institut de Recherche pour le Développment in Nouméa.

Seasonal climate forecasting for Pacific states

 

Floods in Samoa. (Photo: Doug Ramsay, NIWA)

 

The Island Climate Update (ICU) is a NIWA-coordinated monthly climate forecasting service for the South Pacific. The service is targeted at a wide range of users including those tasked with natural hazard and disaster risk management.

Tropical cyclone outlooks and reviews are part of the ICU service. Fortunately the 2007–08 cyclone season, which lasts from November to May, was relatively quiet. Five cyclones were recorded compared to the long-term average of seven. Tropical Cyclone Gene was the most damaging, with seven lives lost in Fiji, widespread power cuts, and US$45 million damage. This season’s strong La Niña conditions have predictably resulted in cyclones tracking further to the west than normal.

The ICU is funded by NZAID, and produced in collaboration with many Pacific Islands’ meteorological organisations. It is freely available at: www.niwascience.co.nz/ncc/icu