2009 a benign year for natural disaster claims

Earthquakes, floods, landslides, and low rainfall, were some of our major hazard events in 2009. For the insurance industry, it was one of the least costly years for natural disasters with claims only totalling $6.75 million, compared with $86.27 million the year before.

The Natural Hazards Centre, a collaboration between NIWA and GNS Science have today published Natural Hazards 2009, a review of New Zealand’s major hazard events.

“It could have been much worse. It was a case of great escapes, with the near-miss of the magnitude 7.8 earthquake in Fiordland in July 2009, - New Zealand’s biggest earthquake in 80 years,” says GNS Science Communications Manager John Callan.

Sadly many New Zealanders were directly affected by the magnitude 8.1 Samoan earthquake and tsunami in September 2009. More than 200 people died as the tsunami ripped through coastal communities in Samoa and Tonga. In several places, the tsunami towered up to 5m above the ground and it travelled inland more than 500m in other locations.

“The devastating hazard events remind us how important it is to be prepared here in New Zealand, the better we can forecast these events, the better off we will be,” says NIWA, Chief Scientist, Natural Hazards, Dr Murray Poulter.

This work by NIWA, GNS Science, and others is about their efforts to reduce the risks, and mitigate the effects, of natural hazards in New Zealand. This is the fourth Natural Hazards Review.

Copies of the Review are available online from www.gns.cri.nz and www.niwa.co.nz

For further information, contact:

Dr Murray Poulter
NIWA, Chief Scientist, Hazards
Tel: 64 4 3860560
Cell: 027 283 3784

John Callan
GNS Science, Communications Manager
Tel: 64 4 570 4732
Cell: 64 027-440-2571

Notes to the editor:

Earthquakes
• In 2009, a total of 42 earthquakes of magnitude 5.0 or greater occurred. It was a quiet year for earthquakes.

• The largest earthquake was the Dusky Sound earthquake (magnitude 7.8); the largest aftershock was magnitude 6.1 and occurred 20 minutes after the main shock.

• There were 188 damage claims lodged for the Dusky Sound earthquake and the total payout by insurers was almost $1 million.

Tsunami
• Four tsunamis were recorded by coastal sea-level gauges around New Zealand, but there was no damage. In order of wave-height size in New Zealand these tsunamis were:

o On 15 July a tsunami originated from Dusky Sound in Fiordland, the result of a magnitude 7.8 earthquake. The highest wave was 0.97m, recorded at Jackson Bay 2.5 hours after the earthquake.

o On 30 September (29 September local Samoan time) a magnitude 8.1 earthquake to the south of Samoa caused the devastating tsunami in Samoa and Tonga. The largest wave recorded was 0.9m at Kaingaroa (Chatham Islands)..

o On 8 October a magnitude 7.3 earthquake in northern Vanuatu caused a small tsunami that was recorded at four sites on the west coast from New Plymouth to Jackson Bay and on the Chatham Islands.

o On 20 March a magnitude 7.3 earthquake south of Tonga caused a small tsunami directed mainly at Chatham Island. It was 0.2m, nine hours after the first wave.

Landslides
• GNS Science recorded over 317 significant landslides, throughout New Zealand. The majority were triggered by the magnitude 7.8 Dusky Sound earthquake on 15 July.
• The others were mostly triggered by rainfall.
• In January two people were killed by an icefall at Fox Glacier
• Thirty slips were reported on SH2 between Napier and Wairoa.

Heavy rain & floods
• Floods are the most common natural hazard in New Zealand
• There were numerous rainfall events during 2009, about 15 of which produced significant flooding.
• Mt Cook received the three highest one-day rainfalls, with 341 mm on 27 April.
• 17 May SH1 south of Ashburton was closed when Rangitata River burst its banks.
• On 18 May farmers near Balclutha used boats to rescue sheep stranded by the flooded Clutha River
• 29 June heavy rain caused slips and closure of SH4.

Snow, hail, & electrical storms
There were many snowfalls across New Zealand.

Snow on 4-6 October in Hawke’s Bay and central North Island saw hundreds of travellers stranded as roads were closed. A local state of emergency was declared.

Temperatures
New Zealand’s climate for 2009 was characterised by frequent see-saws in temperature, but for the year as a whole the national average temperature was 12.3 degrees centigrade.

Avalanches
Winter brought numerous serious avalanches to New Zealand’s mountains, three people were killed, many were injured, buildings were destroyed in a season that saw widespread and persistent avalanche conditions.

Winds & tornadoes
It was a very windy year and, in addition, at least eight tornadoes were recorded. The highest wind gust for the year was 184km/h at Stewart Island.

Low rainfall & drought
Rainfall during the year was below normal (50 to 80 percent of normal) in parts of Auckland, central North Island, northern Hawkes Bay, southern Wairarapa, North Canterbury, inland South Canterbury and Central Otago. Taupo had its driest year since records began. Other areas received near-normal rainfall.

Volcanic activity
It was a quiet year for New Zealand’s volcanoes, with no eruptions onshore, but several short-lived periods of activity at Monowai submarine volcano in the Kermadec Islands.

Coastal Hazards
In 2009, most locations recorded their highest storm tides on 23 July. The cause was a broad depression over New Zealand with strong westerlies impinging on western coasts, coinciding with a high perigean-spring tide.

The highest waves at any of the monitored sites were recorded during one of these winter storms, with significant wave height at Baring Head reaching 7.35m on 23 May.