Tagged: New Zealand in New Zealand - Page 10

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 2001 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.

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.

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 2000 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.

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 2009 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.

Extreme wave indexes estimate the occurrence of extreme wave events in coastal and oceanic waters. Extreme wave indexes estimate the number of times a significant wave height exceeds one of three threshold values for at least 12 hours in 24 marine regions. The three wave-height thresholds are four metres, six metres, and eight metres.
This indicator estimates the exceedances of a wave-height threshold for each year from 2008 to 2015 in coastal regions.
Significant wave height is a measure of the ‘typical’ wave height in a place over a time period. It is four times the standard deviation of the water surface if, for example, you were to measure water moving up and down a jetty piling for an hour. The largest individual wave will typically have a height around twice the significant wave height.
We use three wave-height thresholds because of the regional variation in extreme wave events. In general, the north experiences less exposure to consistently strong winds, and the waves generated by them, than the south. Four-metre tall waves are considered extreme in the northern-most parts of New Zealand but are more common in the south. For the southern-most parts of New Zealand, eight-metre waves better represent extreme wave events.
This dataset relates to the number of extreme wave events exceeding the four metre threshold in coastal regions.

"The pressure from animal and plant pests is one of the biggest threats to biodiversity in the land environment. Pest predators (such as stoats and possums) eat eggs, birds, lizards, insects, and snails. Other animal pests (such as deer and goats) damage and kill trees and other plants and can compete with indigenous animals for the plants’ fruit and seed. Pest plants can out-grow the local vegetation. All these activities can dramatically change both our indigenous and agricultural environments.

This data set relates to the "Land pests" measure on the Environmental Indicators, Te taiao Aotearoa website."

"Freshwater plant and animal pests can have significant negative impacts on ecosystem health by reducing indigenous biodiversity through predation and competition, and destabilising aquatic habitats. Freshwater plant pests can cause economic losses through blocking water intakes for hydroelectricity generation, impeded drainage or irrigation. In addition, pests can affect the suitability for recreational activities.
This dataset relates to the ""Freshwater pests"" measure on the Environmental Indicators, Te taiao Aotearoa website. "

"Freshwater plant and animal pests can have significant negative impacts on ecosystem health by reducing indigenous biodiversity through predation and competition, and destabilising aquatic habitats. Freshwater plant pests can cause economic losses through blocking water intakes for hydroelectricity generation, impeded drainage or irrigation. In addition, pests can affect the suitability for recreational activities.
This dataset relates to the "Freshwater pests" measure on the Environmental Indicators, Te taiao Aotearoa website. "

"Freshwater plant and animal pests can have significant negative impacts on ecosystem health by reducing indigenous biodiversity through predation and competition, and destabilising aquatic habitats. Freshwater plant pests can cause economic losses through blocking water intakes for hydroelectricity generation, impeded drainage or irrigation. In addition, pests can affect the suitability for recreational activities.
This dataset relates to the "Freshwater pests" measure on the Environmental Indicators, Te taiao Aotearoa website. "

Extreme wave indexes estimate the occurrence of extreme wave events in coastal and oceanic waters. Extreme wave indexes estimate the number of times a significant wave height exceeds one of three threshold values for at least 12 hours in 24 marine regions. The three wave-height thresholds are four metres, six metres, and eight metres.
This indicator estimates the exceedances of a wave-height threshold for each year from 2008 to 2015 in coastal regions.
Significant wave height is a measure of the ‘typical’ wave height in a place over a time period. It is four times the standard deviation of the water surface if, for example, you were to measure water moving up and down a jetty piling for an hour. The largest individual wave will typically have a height around twice the significant wave height.
We use three wave-height thresholds because of the regional variation in extreme wave events. In general, the north experiences less exposure to consistently strong winds, and the waves generated by them, than the south. Four-metre tall waves are considered extreme in the northern-most parts of New Zealand but are more common in the south. For the southern-most parts of New Zealand, eight-metre waves better represent extreme wave events.
This dataset relates to the number of extreme wave events exceeding the six metre threshold in coastal regions.