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Rate adjusted to take into account how many old or young people are in a population. When rates are age-standardised, we know that differences in the rates over time or between geographical areas do not simply reflect variations in a population’s age structure. This is important when looking at cancer rates because cancer is a disease that mainly affects the elderly. Without age standardisation, it would be unclear if differing rates were due to age or are a result of other factors.

Area formally notified in the New Zealand Gazette that is likely or known to have unacceptable levels of pollutants, or may require air-quality management.

Form of nitrogen that can be toxic to freshwater organisms at high concentrations.

The average of all values in a range of samples or measurements over a given year.

A temperature anomaly is the difference from an average, or baseline, temperature. Baseline temperature is typically computed by averaging 30 or more years of temperature data. Climate change studies generally use temperature anomalies, rather than absolute temperature.

The practice of farming aquatic organisms such as fish, crustaceans, or molluscs in marine and freshwater environments.

An underground layer of water-bearing rock or sand from which groundwater can be extracted.

Group of islands.

A heavy metal, which in New Zealand comes mainly from burning timber treated with preservative copper-chromate-arsenic. Can be emitted into the air by burning offcuts of treated timber from building projects for home heating. Some industrial processes also emit arsenic.

Species assessed according to the New Zealand Threat Classification System as being at risk of extinction. Includes four subcategories: declining, recovering, relict, and naturally uncommon.

Ecological region of the seafloor, including sediment surface and some sub-surface layers. Extends from the shoreline, seaward along the seafloor, to outer boundaries of New Zealand’s marine environment.

A volatile organic compound. Motor vehicles and home heating are the main sources, and some industrial activities.

A polycyclic aromatic hydrocarbon largely emitted from the combustion of fuels (such as wood and coal from home heating), vehicle emissions, and some industrial processes.

The variability among living organisms, and the ecological systems they are part of. Includes the diversity within species, between species, and of ecosystems.

A biogeographic region with a significant proportion of biodiversity under threat of extinction. To qualify, a region must have at least 1,500 vascular endemic plants and have lost 70 percent or more of its original natural vegetation.

Models that tell us about the physical aspects of the environment, such as how much water is flowing. Also provides information on biological aspects of the environment, such as the presence of E.coli – an important indicator of water quality.

Where the annual average daily traffic count is greater than 20,000 vehicles a day or is a known hotspot for traffic congestion.

Species not targeted by a fishery but caught incidentally during fishing operations. Once caught, they can be landed, discarded, or released.

Campylobacter infection (Campylobacteriosis) is caused by bacteria found in the gut of birds and other animals. It is the most common bacteria causing food-borne illness, passed on in the faeces of infected animals and humans.

Colourless and odourless gas produced by incomplete burning of carbon-containing fuels such as wood, coal, petrol, and diesel.

Area of land in which rainfall drains toward a common stream, river, lake, or estuary.

Change in global or regional climate patterns, evident over an extended period (typically decades or longer). May be due to natural factors or human activities.

Natural fluctuations in global or regional climates that produce recurring climate cycles or patterns. Cycles are generally defined by changes in air pressure, sea temperature, and wind direction over oceans. Climate oscillation periods can vary from a few months to several decades.Climate oscillations affecting New Zealand are the El Niño Southern Oscillation, Pacific Decadal Oscillation, the similar Interdecadal Pacific Oscillation, and Southern Annular Mode.

Measure of the relative quantity of a given substance contained within a specified medium (eg the amount of pollution in the air). Stated as mass per unit volume of air.

When water is taken from a water body and not returned to a water body.

Seabed and subsoil of submarine areas extending out to the continental margin (the zone of the ocean floor that separates the thin oceanic crust from the thick continental crust).

Parasite found in the gut of animals and humans. It is passed on in the faeces of infected animals and humans. Cryptosporidium is widespread in New Zealand.

Highly soluble form of phosphorus.

Total column ozone is measured in Dobson units (DU). One DU represents the amount of ozone molecules needed to produce a 0.01 millimetre layer of pure ozone.

Process of dragging a dredge along the seabed behind a fishing vessel (usually to harvest oysters or scallops).

Sheep, cattle, and deer grazed for meat, wool, and velvet.

Bacteria normally found in the gut of warm-blooded animals and people. Some types can cause illness, such as Campylobacter, which can be transmitted through contaminated water or food, or through contact with infected animals or people.

Ecosystems that generate large amounts of biological material from solar energy.

A community of plants, animals, and microorganisms in a particular place or area, interacting with the non-living components of their environment (like air, water, and mineral soil).

The release of a pollutant into the atmosphere; its concentration in the air will depend on how the pollutant disperses in the atmosphere.

A plant or animal that occurs naturally only in one place or region.

The transport of water into the atmosphere from surfaces, including soil (evaporation), and from vegetation (transpiration).

Where the concentration of a pollutant exceeds a standard or a guideline. A ‘likely exceedance’ is when screening methods are used and the results cannot be used to determine compliance with a standard or guideline.

Area of ocean extending from 12 to 200 nautical milesfrom shore, including the seabed and subsoil. New Zealand has jurisdiction over exploration and extraction of marine resources in its EEZ.

Contact with a chemical, physical, or biological agent that can have either a harmful or beneficial effect.

The part of the continental shelf beyond the EEZ.

The loss of a species. The moment of extinction is generally considered to be marked by the death of the last individual of that species.

Coal, natural gas, liquefied petroleum gas (LPG), crude oil, or a fuel derived from crude oil (including petrol and diesel), so called because they have been formed from ancient organic matterover long periods of time.

Volume and flow rate, measured by continuously monitoring the height of the river surface and converting it to a flow rate.

A slow-moving mass of ice formed by accumulated and compacted snow on mountains or near the North or South poles.

Carbon dioxide, nitrous oxide, methane, ozone, water vapour, and chlorofluorocarbons occurring naturally and resulting from human (production and consumption) activities, and contributing to the greenhouse effect (global warming).

A colourless and odourless gas produced by other gases reacting in the presence of sunlight. Examples of pollutants that form ozone are oxides of nitrogen and volatile organic compounds caused by transport, home heating, and industrial processes.

Water located beneath Earth's surface in pore spaces (the spaces within a rock body that are not occupied by solid material) and fractures of rock formations.

Total days over a year in which the mean daily temperature is higher than a base value (10 degrees Celsius).

Guidelines provide recommendations that outdoor air quality should meet. Unlike standards, they are not required by law to be met. We used national and international guidelines (the Ministry for the Environment’s 2002 Ambient Air Quality Guidelines and the World Health Organization (WHO) guidelines in this report to compare long-term concentrations. We used the WHO guidelines to compare short-term concentrations where they differ from the national standards.

Subset of elements that exhibit metallic properties and have relatively high atomic weight. Heavy metals can be emitted from human activities, such as vehicle tyre/brake wear and battery and steelmaking facilities, but some also occur naturally in the air.

Amount of water vapour in the air. Water vapour is the gaseous state of water and indicates the likelihood of precipitation, dew, or fog.

Belonging naturally to a given region or ecosystem, as opposed to an animal or plant that is exotic or introduced. Also referred to as ‘native’.

Commonly known as ‘the flu’, influenza is a virus that spreads quickly from person to person, and in serious cases, can cause death. In temperate climates such as New Zealand’s, people are more likely to get the flu in winter.

An animal without a backbone or spinal column. Insects, spiders, worms, slaters, and many marine animals such as corals, sponges, and jellyfish are examples of invertebrates.

Small animal that has no backbone and can be seen with the naked eye (eg insects, freshwater crayfish, snails, and worms).

An indicator of general river health: excellent >119;good 100–119; fair 80–99; poor <80.

The knowledge, comprehension, or understanding of everything visible and invisible existing in the universe, and often used to mean ‘wisdom’. Often includes present-day, historic, local, and traditional knowledge; systems for transferring and storing knowledge; and goals, aspirations, and issues from an indigenous perspective.

The midpoint of a series when the data are listed in ascending order. Half the numbers or values are above the midpoint, and half are below it.

Unit of density used to measure volume in cubic millimetres to estimate weight or mass in micrograms.

A unit of length equal to one-thousandth of a millimetre. Also called a micron.

Site where equipment is deployed to sample and/or measure the quality of air or water.

Standards set by the government to help maintain a clean, healthy environment. National standards for air quality set minimum requirements for outdoor air quality in New Zealand, with a maximum concentration that a pollutant can be experienced at and the allowable number of times this maximum concentration can be exceeded in a year. We used the national standards in this report to compare daily and hourly concentrations.

Species whose distribution is naturally confined to specific habitats or geographic areas, or which naturally occur in small and widely scattered populations.

Highly soluble form of nitrogen that is both a nutrient and, in excess quantities, a toxic substance.

Nutrient essential for plant and animal life. Too much can cause large amounts of weeds and algae to grow, harming river health. In some forms can be toxic to fish and other aquatic animals.

Reddish-brown, pungent gas produced mainly from the combustion of fossil fuels (coal, gas, diesel, and oil) and some industrial processes. It can be emitted directly into the air but is most often formed when nitric oxide emissions react with other chemicals in the air. Collectively, nitrogen dioxide and nitric oxide are referred to as nitrogen oxides.

Collective term for nitrogen dioxide and nitric oxide. Nitric oxide often makes up the larger component, but is readily converted to nitrogen dioxide in the environment.

When sediment becomes enriched as a result of nutrients being leached or deposited.

Rate of fishing that exceeds the rate at which the stock is naturally replenished and will lead to a stock falling below management targets and/or limits.

Pungent, colourless, toxic gas that occurs naturally at a concentration of about 0.01 parts per million of air. Levels of 0.1 parts per million are considered to be toxic. In the stratosphere, ozone provides a protective layer shielding Earth from the harmful effects of ultraviolet radiation. In the troposphere, it is a major component of photochemical smog, which seriously affects the human respiratory system.

Substance that depletes the ozone layer, such as chlorofluorocarbon.

Small airborne particles composed of solid and/or liquid matter.

Measure of acidity/alkalinity, with measures below 7 being acid and above 7 being alkaline.

Nutrient essential for plant and animal life. Too much can cause large amounts of weeds and algae to grow, harming river health.

Process where plants use light energy from the sun to convert carbon dioxide, water, and minerals to sugar, which they use as energy to grow and release oxygen.

Airborne particle 10 micrometres or less in diameter (about one-fifth the thickness of a human hair). Produced by the combustion of wood and fossil fuels, as well as by various industrial and natural processes.

Airborne particle 2.5 micrometres or less in diameter and mostly come from combustion sources (see PM10 particles). Most particulate matter from natural sources is larger than 2.5µm in diameter.

Discharge from a fixed source such as an effluent pipe, as opposed to diffuse discharges such as agricultural run-off from land.

Any substance (including gases, odorous compounds, liquids, solids, and microorganisms) or energy, or heat, that causes an undesirable change to the physical, chemical, or biological environment.

Primary mechanism for transporting water from the atmosphere to Earth’s surface. Includes rain, sleet, snow, and hail.

The amount of organic matter produced by plants and some microorganisms.

System established in 1986 to control the total commercial catch for most of the main fish stocks in New Zealand’s exclusive economic zone.

Species that breed in New Zealand.

Bacteria that causes the infection salmonellosis. It is the second most-common bacteria that causes food-borne illness in New Zealand. Salmonella bacteria live in the gut of many farm animals and can contaminate meat, eggs, poultry, milk, and other foods.

Any non-standard method that provides indicative data for a particular contaminant. It uses low-resolution instruments and cannot be used to determine compliance with a standard or guideline.

Pollution of water by fine suspended sediment and the accumulation of fine sediment on the bottom of a seafloor or estuary, where it can smother plants or animals.

A basic unit of biological classification, comprising individual organisms that are very similar in appearance, anatomy, physiology, and genetics, due to having relatively recent common ancestors. Species can interbreed.

Air-quality monitoring method recommended by a national or international body that can be used to determine compliance with a standard or guideline.

When a finding is likely to be due to something other than random chance. A statistically significant finding is determined by tests based on the 95 percent confidence interval. This interval shows the range of values that would include the estimate 95 percent of the time if the test was repeated multiple times.

Upper layer of the atmosphere, from about 10 to 50 kilometres above Earth’s surface. The stratosphere is almost completely free of clouds or other forms of weather.

Geographically isolated population that interbreeds and is part of a species.

Colourless gas with a pungent smell, produced during the combustion of fuels containing sulphur, such as coal and diesel.

Occurs when a layer of warm air sits over a layer of cooler air near the ground. Because cool air is heavier than warm air, it often remains trapped close to the ground. Air pollution that gets trapped beneath the inversion layer can build up, increasing air pollution concentrations.

Area of sea extending from the coast to the 12 nautical mile limit.

Species assessed according to the New Zealand Threat Classification System as being threatened with extinction. Includes three subcategories: nationally critical, nationally endangered, and nationally vulnerable.

Total amount of ozone in a column from the surface of Earth to the edge of the atmosphere.

Process of dragging a trawl net behind a fishing vessel, along or just above the seabed.

An indication of the level of nutrient enrichment (excessive amounts of nutrients) of a lake, based on the growth of plants and algae.

Lowest layer of Earth's atmosphere, where almost all our weather develops. Extends about 10 kilometres upward from Earth’s surface and contains 75 percent of the atmosphere's mass and most of its water vapour.

Light in the wavelength range between visible light and X-rays. The ozone layer prevents a large amount of UV light from reaching Earth’s surface.

Plants that have developed a system to transport water and nutrients. These include plants with flowers and cones, ferns, horsetails, and clubmosses. They exclude algae, hornworts, liverworts, and mosses.

Animal with a backbone. Includes amphibians, reptiles, birds, mammals, and fish.

Any compound of carbon (excluding carbon monoxide, carbon dioxide, carbonic acid, metallic carbides or carbonates, and ammonium carbonate) that participates in atmospheric photochemical reactions.

Activity with a low risk of full immersion in fresh water (eg accidental immersion while walking (wading) through water for exercise, or standing in water while fishing).

Measure of the underwater range of vision in freshwater systems such as rivers and streams.