Marine Data

The average concentration of chlorophyll-a (chl-a) in phytoplankton over the period 1997 to February 2016.
Concentrations of chl-a in phytoplankton are used to assess primary productivity in our oceans. Phytoplankton are primary producers of biomass (mass of living organisms) and form the main basis of marine food chains. They use the chl-a pigment to capture the sun’s energy through the process of photosynthesis. Phytoplankton growth is affected by the availability of nutrients and light, which in turn are affected by the structure of the surface water column. The surface water column structure is affected by oceanographic and climate processes; large-scale changes to climate and oceanographic conditions can lead to changes in phytoplankton growth and chl-a concentrations.

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 (MPAs) 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.
Type 2 MPAs have lower levels of protection than marine reserves. For example, they may allow fishing but restrict seabed trawling.

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

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.
Seamount (underwater mountain area) closures are one of the marine protection tools used. They are designated areas in the exclusive economic zone, which extends to the 200 nautical mile limit. Seamount closures protect underwater mountain areas through the prohibition of all trawling activity. There are some areas where seamount closures overlap with benthic protection areas. In these cases the seamount closure restrictions apply.

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.

The location and extent of seamount closures designated in the exclusive economic zone.

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 wave-height thresholds for each year from 2008 to 2015 in oceanic regions around New Zealand.
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 oceanic regions.

The 15 class Benthic-Optimised Marine Environment Classification (BOMEC). The BOMEC divides the benthic environment into ecosystem types. These are grouped into three inshore groups, three continental shelf groups, and nine deeper-water groups. Each group represents areas with similar environmental variables, such as depth, temperature, salinity, and suspended sediment. The classification system considers the distributions of eight benthic taxonomic groups: asteroids, bryozoans, benthic foraminiferans, octocorals, polychaetes, matrix-forming scleratinian corals, sponges, and benthic fish.