Oceania Atmosphere & Climate Data

Annual rainfall is the total accumulated rain over one year. Rain is vital for life, including plant growth, drinking water, river ecosystem health, and sanitation. Floods and droughts affect our environment, economy, and recreational opportunities.

This dataset shows annual average rainfall across New Zealand for years 1972 to 2013. Annual rainfall is estimated from the daily rainfall estimates of the Virtual Climate Station Network (NIWA).

This dataset relates to the "Annual average rainfall" measure on the Environmental Indicators, Te taiao Aotearoa website.

Geometry: raster catalogue
Unit: mm/yr

Rain is vital for life – it supplies the water we need to drink and to grow our food, keeps our ecosystems healthy, and supplies our electricity. New Zealand’s mountainous terrain and location in the roaring forties mean rainfall varies across the country. Changes in rainfall amount or timing can significantly affect agriculture, energy, recreation, and the environment. For example, an increase or decrease of rainfall in spring can have marked effects on crops or fish populations.
More information on this dataset and how it relates to our environmental reporting indicators and topics can be found in the attached data quality pdf.

Lightning is the discharge of electricity, from thunderstorms, that equalises areas of positive and negative charge, for example, between a storm cloud and the ground. Thunderstorms form as a result of rapidly rising air with a high moisture content (humidity). On average, 1 in 10 lightning discharges strikes the ground (or sea) (Metservice, 2015). Lightning (and therefore thunderstorms) are also often associated with other severe weather events, such as strong wind gusts, and in extreme cases tornadoes.

By international standards, lightning does not occur frequently around New Zealand. However, thunderstorms, and thus lightning, can cause injury and damage (Ministry of Civil Defence and Emergency Management, 2010), and may increase in frequency and intensity with climate change (Mullen et. al., 2011).

This data shows the average annual number of lightning strikes per 25km square.

This dataset relates to the "Lightning" measure on the Environmental Indicators, Te taiao Aotearoa website.

Geometry: grid/point

Unit: strikes/25km2/year

Further information can be found in:

MetService (nd). Lightning observation services. Accessed 3 June 2015 from www.metservice.com.

Ministry of Civil Defence and Emergency Management (2010). Thunderstorms. Working from the same page: Consistent messages for CDEM (p3). Available from www.civildefence.govt.nz.

Mullan, B, Carey-Smith, T, Griffiths, G, & Sood, A (2011). Scenarios of storminess and regional wind extremes under climate change. NIWA Client Report: WLG2010-31 (pvii). Available from www.niwa.co.nz.

Soil moisture is important for plant growth. A lack of moisture content over a growing season is a good indicator of drought, which can have social, environmental, and economic impacts. Increasing temperatures and changes in rainfall patterns are expected to increase the frequency and intensity of drought in many regions. Growing season soil moisture deficits are estimated by the potential evapotranspiration deficit, the difference between rainfall and evapotranspiration.

This dataset shows annual average soil moisture (potential evapotranspiration deficit (PED)) across New Zealand for years 1972 to 2014.

Evapotranspiration is the loss of water by evaporation and plant transpiration. PED is the difference between estimated evapotranspiration and rainfall.

We produced maps of the annual PED total (in millimetres) for every growing season (calculated as July–June years) from 1972 to 2013. Care should be taken when comparing maps from year to year – days may be missing from the PED GIS data, and data may have been interpolated to complete the dataset. The interpolation accuracy is lowest in areas of high elevation, where there are fewer climate stations and complex terrain affects accuracy. Climate stations may also open and close, affecting the accuracy of the data provided.

This dataset relates to the "Soil moisture and drought" measure on the Environmental Indicators, Te taiao Aotearoa website.

Geometry: raster catalogue
Unit: mm/yr

Rain is vital for life – it supplies the water we need to drink and to grow our food, keeps our ecosystems healthy, and supplies our electricity. New Zealand’s mountainous terrain and location in the roaring forties mean rainfall varies across the country. Changes in rainfall amount or timing can significantly affect agriculture, energy, recreation, and the environment. For example, an increase or decrease of rainfall in spring can have marked effects on crops or fish populations.
More information on this dataset and how it relates to our environmental reporting indicators and topics can be found in the attached data quality pdf.

Lightning is the discharge of electricity from thunderstorms. Ground strikes can cause significant damage to property and infrastructure, and injure or kill people and livestock. Lightning is often associated with other severe weather events, such as strong wind gusts. Thunderstorms may increase in frequency and intensity with climate change.

This dataset shows the location of sensors in the New Zealand Lightning Detection Network (NZLDN), run by MetService.

Sensors around the country detect lightning over the New Zealand land mass and a short distance out to sea. These sensors detect very accurately the electrical discharge, location, and time, as well as noting other parameters such as current strength. The NZLDN records both cloud-to-cloud and cloud-to-ground strikes.

Lightning is the discharge of electricity from thunderstorms. Ground strikes can cause significant damage to property and infrastructure, and injure or kill people and livestock. Lightning is often associated with other severe weather events, such as strong wind gusts. Thunderstorms may increase in frequency and intensity with climate change.
This dataset relates to the "Lightning" measure on the Environmental Indicators, Te taiao Aotearoa website.

The ocean waters surrounding New Zealand vary in temperature from north to south. They interact with heat and moisture in the atmosphere and affect our weather. Long-term changes and short-term variability in sea-surface temperatures can affect marine processes, habitats, and species. Some species may find it hard to survive in changing environmental conditions.

This layer shows annual sea-surface temperature difference from normal for 2007 as part of the data series for years 1993 to 2013. "Normal" is defined as the average sea-surface temperature for 1993–2013.

NIWA’s sea-surface temperature archive is derived from the Advanced Very High Resolution Radiometer (AVHRR) satellite data it receives from the National Oceanic and Atmospheric Administration. The archive provides high spatial (approximately 1km) and high temporal (approximately 6-hourly in cloud-free locations) resolution estimates of sea-surface temperatures over the New Zealand region, dating from January 1993. Uddstrom and Oien (1999) and Uddstrom (2003) describe the methods used to derive and validate the data.

This dataset relates to the "Annual average sea-surface temperature" measure on the Environmental Indicators, Te taiao Aotearoa website.

Geometry: grid

Unit: percent

Further information can be found in:

Uddstrom, MJ (2003). Lessons from high-resolution satellite SSTs. Bulletin of the American Meteorological Society, 84(7), 896–897.

Uddstrom, MJ, & Oien, NA (1999). On the use of high resolution satellite data to describe the spatial and temporal variability of sea surface temperatures in the New Zealand region. Journal of Geophysical Research (Oceans) 104, chapter 9, 20729–20751.

"Annual rainfall is the total accumulated rain over one year. Rain is vital for life, including plant growth, drinking water, river ecosystem health, and sanitation. Floods and droughts affect our environment, economy, and recreational opportunities.

This dataset shows annual average rainfall across New Zealand for 2013 as part of the data series for years 1972 to 2013. Annual rainfall is estimated from the daily rainfall estimates of the Virtual Climate Station Network (NIWA).

This dataset relates to the "Annual average rainfall" measure on the Environmental Indicators, Te taiao Aotearoa website.

Geometry: grid
Unit: mm/yr"

Potential evapotranspiration deficit (PED) can be thought of as a drought index. It is the difference between how much water could potentially be lost from the soil through evapotranspiration and how much is actually available. When PED is high, plants do not have the full amount of water available they need for growth. As our climate changes, increasing temperatures and rainfall pattern changes are expected to increase PED, and the frequency and intensity of drought, particularly in currently drought-prone regions.
More information on this dataset and how it relates to our environmental reporting indicators and topics can be found in the attached data quality pdf.