Tagged: science environment in World

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 location and extent of Marine reserves (type 1 marine protected areas) in the territorial sea.

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.

New Zealand’s four million km2 marine environment is diverse, with a range of coastal habitats and offshore seabed environments. There are also many marine species unique to New Zealand. Marine protected areas conserve or manage some of these unique habitats and species, while a range of other tools also provide marine protection. We report on the area covered by these tools as an indirect measure to understand the state of the marine environment.
Marine reserves lie within our territorial sea (12 nautical mile limit) and offer the highest level of marine protection in New Zealand waters. No marine habitat or life form, such as seaweed or fish, may be removed from, or disturbed in, these places.

New Zealand’s four million km2 marine environment is diverse, with a range of coastal habitats and offshore seabed environments. There are also many marine species unique to New Zealand. Marine protected areas conserve or manage some of these unique habitats and species, while a range of other tools also provide marine protection. We report on the area covered by these tools as an indirect measure to understand the state of the marine environment.
Benthic protection areas (protected seabed areas) are one of the marine protection tools used. They are designated areas in the exclusive economic zone, which extends from the 12 nautical mile seaward limit of the territorial sea to the 200 nautical mile limit. Bethnic protection areas protect seabed habitats through the prohibition of bottom trawling and dredging. There are some areas where seamount closures overlap with benthic protection areas. In these cases the seamount closure restrictions apply.
Note that the thumbnail preview of this spatial data does not reflect the data underlying it. Please see the methodology for a more reflective preview.

The location and extent of Type 2 marine protected areas in the territorial sea.

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 eight metre threshold in coastal regions.

"The average concentration of chlorophyll-a (chl-a) in phytoplankton for 2014.
Concentrations of chl-a in phytoplankton are used to assess primary productivity in our oceans. Phytoplankton are primary producers of biomass and form the basis of the oceans’ food chains."

The location and extent of Marine mammal sanctuaries in the territorial sea and the exclusive economic zone.

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 oceanic 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 eight metre threshold in oceanic regions.