Hazards

A summary of the areas of hazards research at NIWA.

Coastal hazards: exposure, impacts and risk

Coastal hazards, driven by more extreme coastal physical processes (including coinciding factors), can cause damage, disruption and even casualties in estuaries, river mouths, open coasts and coastal/shelf waters.

Planning for coastal adaptation

While much of the global focus and discussion around climate change has been on mitigating (reducing) greenhouse gas emissions, adaptation has now become an integral part of climate change policy worldwide.

Sea levels and sea-level rise

Heat is being trapped in the atmosphere by increasing concentrations of carbon dioxide (CO2) and other greenhouse gases, and the climate–ocean and ice systems are responding. One of the major and most certain (and so foreseeable) consequences is the rising sea level.

Storm-tide red-alert days 2020

The 2020 storm-tide "red-alert" dates are "king-tide" days that Emergency Managers and Coastal Hazard Managers should write in their diaries and keep an eye on adverse weather (low barometric pressure, onshore winds), river levels and sea conditions (waves and swell).

Coastal storm inundation

New Zealand has low-lying coastal areas that are vulnerable to inundation (flooding) by the sea, especially during storms.

Droughts

Generally speaking, a drought is defined as a rainfall deficit which restricts or prevents a human activity – for example, farming or power generation.

Extreme weather - heavy rainfall

Heavy rainfall is one of the most frequent and widespread severe weather hazards to affect New Zealand. It is defined as rainfall greater than 100 mm in 24 hours.

Extreme weather - winds and tornadoes

Due to its position in the 'Roaring Forties', a belt of strong winds in the Southern Hemisphere which generally occur between the latitudes of 40 and 49 degrees, as well as its small size, New Zealand is a windy country.

Floods

River floods occur when water spills from a river channel onto land that is normally dry, and are one of New Zealand's costliest natural hazards.

Marine geological hazards

New Zealand faces a variety of hazards associated with undersea geological activity.

Risk and vulnerability

Risks from natural hazards are part of every day life for New Zealanders, whether it is from floods, storms, tsunami, landslides, severe weather or earthquakes.

Snow and avalanches

New Zealand faces a variety of hazards associated with snow.

Tsunami

Coming from the Japanese word 'harbour wave', tsunami are a series of waves – with wave lengths up to hundreds of kilometres between crests - caused by undersea seismic disturbances.

Waves

The waters around New Zealand have some of the highest waves in the world, being exposed to swell coming up from the Southern Ocean, as well as storms in the Tasman Sea and Pacific Ocean.