Environmental Reporting Data - Page 9

The status of our bird communities is an important indicator for the condition of our ecosystems. Many indigenous birds play key ecological roles, including dispersing seeds and pollinating flowers. In some situations, exotic (not indigenous to New Zealand) bird species can partially fulfil these roles. Measuring the composition of bird communities across public conservation land allows us to monitor how those communities are changing over time.

This data set relates to the "Bird species on public conservation land" 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 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.

"This data identified areas in the South Island that have been classified as being the most productive for growing food. It supports most crops across New Zealand. Expanding lifestyle blocks and urban areas reduce the availability of high-class land for commercial crop growing, and this land is unlikely to be returned to primary production. This affects our commercial food-production capacity.

This data set relates to the "High-class land for food production" measure on the Environmental Indicators, Te taiao Aotearoa website."

Coastal and estuarine ecosystems are affected by changes in the levels of nutrients, oxygen, and light. An overload of nutrients can be toxic or lead to algal blooms. These blooms can kill marine life by depleting oxygen levels. Suspended sediment can smother habitats or reduce light levels, affecting photosynthesis. We report on five measures of water quality: turbidity (murkiness), dissolved oxygen, and the dissolved nutrients nitrate- and nitrite-nitrogen, ammoniacal nitrogen, and total phosphorus.
This dataset relates to the "Coastal and estuarine water quality" 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 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.

Too much exposure to the sun's ultraviolet (UV) radiation can cause skin cancer. Ozone absorbs some UV radiation, and UV levels can vary in relation to changes in atmospheric ozone. Monitoring UV levels can help us understand current skin cancer risk.
The most reliable data on solar UV irradiance in New Zealand are from spectroradiometers developed and operated by NIWA at Lauder since summer 1989/90. The dataset supplied begins in 1993, and measurements includee daily peak, noon-time mean, and total daily dose of erythemal (skin-reddening) UV.
Further information can be found in:
Liley, B, Querel, B, & McKenzie, R (2014). Measurements of Ozone and UV for New Zealand. Prepared for the Ministry for the Environment, Wellington. Available at data.mfe.govt.nz/x/LoPyPo on the Ministry for the Environment dataservice (data.mfe.govt.nz/).
This dataset relates to the "UV intensity" measure on the Environmental Indicators, Te taiao Aotearoa website.

Land cover describes the extent of vegetation, water bodies, built environment, and bare natural surfaces (eg gravel and rock) across New Zealand. Measuring the composition and changes in land cover can help us better understand the pressures that different land uses are placing on the biodiversity and functioning of ecosystems.

Column headings:
area_ha = area of land cover measured in hectares

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

A consistent band of westerly wind flows across the Southern Hemisphere and circles the South Pole. The Southern Annular Mode (SAM) describes how this band moves, either north towards the equator (negative phase) or south towards Antarctica (positive phase). A negative phase typically causes increased westerlies, unsettled weather, and storms in New Zealand. A phase can last several weeks, but changes can be rapid and unpredictable.
The SAM is one of three climate oscillations that affect our weather. The resulting changes in air pressure, sea temperature, and wind direction can last for weeks to decades, depending on the oscillation.
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.

Percent of land deforested in each Territorial Authority unit from 2008–2014. New Zealand’s indigenous and exotic forests absorb carbon dioxide (CO2) from the atmosphere through photosynthesis and store the carbon as biomass and in the soil. On average, more than twice as much carbon per hectare is stored in New Zealand’s mature indigenous forests than in exotic forests planted for wood production. Regenerating indigenous forests are also an important store of carbon, adding carbon every year as they grow. Total carbon stored in exotic forests will fluctuate over decades as the forests grow from seedlings to mature trees, are harvested, and replanted. Because CO2 is the major driver of climate change, forests provide important mitigation services and help New Zealand meet its climate change commitments.
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.

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.