Natural disasters in New Zealand: past and future risks
New Zealand has traditionally been a very popular tourist destination. Every year the number of people who come to the islands to relax on the beaches, get acquainted with the culture and customs of the aborigines and admire the beautiful nature increases. They should find out in advance what kind of natural disasters or catastrophes they may encounter. Disaster always comes unexpectedly, but knowing its potential can help you prepare for it.
Climatic features of New Zealand
The islands of New Zealand lie in the Southern Hemisphere in the Western Pacific Ocean. They are characterised by two types of climate: subtropical in the north and temperate in the south.
For these climate types, the annual variation in mean temperatures is already becoming quite high. In the winter months (June-August for the Southern Hemisphere), air and water temperatures drop significantly. The air temperature drops to 10-15 degrees Celsius and water temperature to 13-16 degrees Celsius.
Humidification for these climate types is largely uniform, with rainfall scattered throughout the seasons. However, the summer months (December-February) are traditionally more humid. Torrential downpours, strong hurricanes and storms are not uncommon at this time.
The basin of tropical cyclones is north-eastwards, but some of them reach New Zealand.
The relief of the islands is predominantly mountainous. On the North Island there are fewer mountains, on the South Island – a mountain range stretches across the island.
New Zealand lies at the junction of the Australian and Pacific lithospheric plates, the mutual movement of which leads to seismic and volcanic activity.
Large parts of the islands are covered with dense forests, with coniferous forests in the mountains.
Potentially hazardous factors that can cause a natural disaster include:
- Seismic activity. The collision of two lithospheric plates, on the border of which the archipelago is located, threatens with strong earthquakes and tsunamis.
- Large length of the coastline. Threatens the country with flash floods, tsunami strikes, landslides and other troubles.
- Volcanism. New Zealand’s location in the zone of the Pacific Ring of Fire leads to strong volcanic activity.
- Seasonal hurricanes and storms. Bring strong winds and heavy rainfall, damaging coastal infrastructure.
- Heavy rains and snowfall. Can cause short-term flooding and mountain river overflows.
- High mountains. Increase the likelihood of landslides and rockfalls, threatening transport links and settlements.
- High forest cover. There is a probability of occurrence and spread of forest fires.
The importance of studying the history of natural disasters
The history of natural disasters is important information to learn before travelling to your chosen country. Knowing about the potential dangers that may await you will not only help you choose the right place, but also the time and season of the year when the threat of being in the epicentre of a natural disaster will be minimal.
For example, knowing that the rainy and hurricane season, when floods are most common, starts in November and lasts until March, you can choose a different time to travel to New Zealand.
From this article, you will learn the chronology of natural disasters that have occurred on the island in the past.
Earthquakes and tsunamis
There are several thousand seismic events detected by sensors every year. But only a small fraction of them pose any threat. And very strong, destructive earthquakes occur no more than once a decade.
3 February 1931, Hawkes Bay
The epicentre of the earthquake was 15 kilometres from the town of Napier. The intensity of the tremors exceeded 7.5 points. As a result, the city of Napier was almost wiped off the face of the earth, in some places the ground rose to 2 metres. Due to numerous destructions in the city, a strong fire broke out. A total of 256 people died.
4 September 2010, Canterbury
The 7.1 magnitude tremors lasted 40 seconds and were felt across the South Island and parts of the North Island. Buildings were destroyed in a number of towns, Christchurch International Airport was closed and thousands of residents lost power. In the town of Darfield, which was at the epicentre, there was a 4-metre ground shift. There were no fatalities, but about 100 people were injured.
22 February 2011, Christchurch
The epicentre of this earthquake was only 10 kilometres from the centre of Christchurch, with a magnitude of 6.3. The destructive effects were amplified by the shallow depth of the earthquake source – only 5 kilometres. As a result, many buildings in the city were destroyed, 185 people were killed under the rubble, the tremors were felt throughout the South Island.
4 March 2021, Kermadec Islands
These islands are part of New Zealand, but are located far to the north. In March 2021, two earthquakes with magnitudes approaching magnitude 8 occurred here. Their epicentre was near Raoul Island. As a result, dozens of landslides occurred, but there were no casualties, as the island itself was uninhabited. The earthquake caused a small tsunami, which did not reach New Zealand.
The volcanic activity of the New Zealand archipelago is due to its location on the boundary between the Indo-Australian and Pacific lithospheric plates. Almost all active and dormant volcanoes in the region are located on the North Island. There are no active volcanoes on the South Island.
26,500 years ago, Taupo volcano
This eruption is considered the strongest not only in the history of New Zealand, but also in the world for the last 70,000 years. It spewed more than 1,000 cubic kilometres of magma. Volcanic ash spread over 1000 kilometres and even on the Chatham Archipelago lay a layer of 18 centimetres. All this allowed volcanologists to classify this eruption as a super eruption. Currently, the Taupo volcano on the North Island is considered dormant.
10 June 1886, Tarawera volcano
This was the last eruption to date of this volcano, located on the North Island. The eruption was accompanied by violent tremors, and the lava flows, which rushed out in three tongues, destroyed several Maori settlements at the foot. About 150 people, mostly Aboriginal people, died as a result.
9 December 2019, Isle of Wight
The explosive eruption of the Whakaari volcano came as a complete surprise to the authorities. The Isle of Wight was popular with tourists, and at the time several groups totalling around 50 people were on the island. As a result, 22 people died.
Storms and hurricanes
Hurricane season starts in New Zealand in December and usually lasts until March. The risk of being at the centre of a storm increases at this time, but most days are fine.
1-6 February 1868
The hurricane that occurred during those days was called the Great Storm. Scientists believe that it was caused by an extratropical cyclone that reached the coast of the archipelago. The storm swept across the country, causing great destruction. The wind tore trees and ripped roofs off houses. The downpours that accompanied the storm caused a number of floods. Six ships sank at sea. The total death toll was 40 people.
10 April 1968, Cyclone Giselle
This was one of the strongest cyclones ever to hit the country. In the Wellington area, wind gusts reached 270 kilometres per hour. In an instant, hundreds of homes lost their roofs and winds toppled cars, hindering ambulance services. At the exit of Cook Strait, a passenger ship was thrown onto a reef and sank. Fifty-three people died.
6-10 March 1988, Cyclone Bhola
This cyclone was the heaviest rainfall event in recorded history. Half a year’s worth of rainfall fell in a short period of time over parts of the North Island. Rainfall totals reached 900 millimetres in some places. In Gisborne, the cyclone destroyed several bridges and roads, forcing residents to evacuate. A car was washed away by floodwaters, in which 3 people drowned.
12-16 February 2023, Cyclone Gabriel
This cyclone proved to be the most costly in its aftermath. Taking over the entire North Island, the cyclone destroyed thousands of homes, washed away bridges and roads, and swept cars into the sea. Agricultural farms were badly damaged. Thousands of people were evacuated. The cyclone killed 11 people and caused a total loss of $8 billion.
Floods caused by rain and snowfall
Due to the peculiarities of the geographical location of the archipelago on its islands, both torrential downpours in summer and heavy snowfalls in winter are possible. However, as New Zealand lies partly in the subtropical belt, snowfalls are rare.
Unusually snowy weather led to a series of devastating floods in the South Island that year. Fortunately, the population density was very low in those years, but the floods managed to destroy several gold mining settlements. About 50 people lost their lives.
20 December 1976
Heavy rain that lasted for several hours caused an unprecedented rise in the Hutt River. The surging river tore down bridges and swept away houses. Services between Wellington and a number of towns were disrupted. About 350 millimetres of rain fell in 24 hours. As a result, a boy was killed when the wall of his own house collapsed.
14-16 February 2004
Heavy rains accompanied by hurricane-force winds led to flooding in the area of the country’s capital. Floodwaters inundated vast areas of agricultural land and rendered hundreds of people homeless. Livestock farming was severely damaged, with herds of sheep and cows being swept out to sea. A state of emergency was declared in three regions of the country, and more than 500 people were hurriedly evacuated.
25 July 2011
The coldest summer in this century was marked by the strongest snow storms. Snowfalls blanketed the nation’s capital Wellington for the first time since 1976. Snow fell even in Auckland, which is unprecedented in the history of meteorological observations.
Due to the high forest cover in much of the country, the threat of fires is very relevant here. On 5 February 2019, for example, a large fire broke out near the town of Pigeon Valley in the south of the country. The fire quickly engulfed 2,400 hectares of forest, making the fire the largest in 60 years. The fire is believed to have been brought under control on 6 February, but extinguishing individual pockets of the fire continued until early March. No one was killed as a result, but a firefighting helicopter crashed.
The biggest threat to tourists holidaying in New Zealand is earthquakes. This natural disaster occurs regularly, but fortunately is not characterised by high intensity. The eastern coast of the South Island suffers the most from earthquakes.
Volcanic eruptions are also of great potential danger. There are six volcanic fields in the country, and there are volcanoes on individual islands. For example, the volcanic field around Auckland invariably attracts tourists. The last eruption in this region took place 700 years ago and now all volcanoes here are considered dormant. But the period of their activation can happen suddenly, at any time, not in our century, so in the next.
Tropical cyclones reach New Zealand’s eastern shores every few years, most of them affecting the North Island. They bring strong winds and heavy rainfall. However, heavy rainfall is also common on the west coast of the South Island. The associated flooding affects many towns.
Forest fires do not pose a serious threat to tourists, but are more likely to affect the southern regions.
The best time to visit New Zealand is from December to March. Although heavy rains and storms are common, the number of sunny days is high and temperatures are comfortable. Between May and September, the water gets too cool, making beach activities impossible.