NIWA supplied ozone data in two forms, with different starting dates: - measurements made using a Dobson spectrophotometer (number 72), from 1987 - data assimilated from satellite measurements recalibrated against the global Dobson network, from 1978. NIWA takes measurements using the Dobson spectrophotometer 72 under clear-sky, direct sunlight conditions...

Urban water quality indicators include heavy metals, nutrients, and E.coli. The concentrations of these indicators are compared to the proportion of urban land cover in catchments. Heavy metals have the ability to accumulate in sediments, shellfish, and other aquatic organisms. Metals can reach toxic levels in organisms making them unsafe to consume and...

New Zealand waters have at least 113 species of chondrichthyans (sharks, rays, and other cartilaginous fish species). They are particularly vulnerable to overfishing because they are long-lived, mature slowly, and have a low reproductive rate. Chondrichthyans are important for healthy ocean ecosystems, and reporting their commercial catch and bycatch...

Autumn rainfall trends for 30 representative sites from 1960–2016. Rain is vital for life – it supplies the water we need to drink and to grow our food, keeps our ecosystems healthy, and supplies our electricity. New Zealand’s mountainous terrain and location in the roaring forties mean rainfall varies across the country. Changes in rainfall amount or...

Ozone (O3) is a gas that is of interest in two regions of Earth’s atmosphere – at ground level and in the upper atmosphere (stratosphere). Stratospheric ozone absorbs ultraviolet (UV) rays from the sun and protects Earth from harmful levels of UV. Exposure to these UV rays has been linked to skin cancer. Monitoring variations in stratospheric ozone...

Freshwater fish are an important component of freshwater ecosystems and a valued resource for Māori and recreational fishers. The community of fish species found at a site can be affected by changes in catchment land cover and land use, in-stream habitat, fish passages (routes for moving up and down waterways), pests, and contaminants. The fish index of...

DATA SOURCE: National Institute for Water and Atmospheric Research (NIWA) [Technical report available at https://www.mfe.govt.nz/publications/environmental-reporting/ministry-environment-atmosphere-and-climate-report-2020-updated] Adapted by Ministry for the Environment and Statistics New Zealand to provide for environmental reporting transparency Dataset...

Sulphur dioxide (SO2) is a gas produced from human (eg industry and shipping) and natural (geothermal and volcanic) activities. Nationally, the main human-made source of sulphur oxides emissions is industry. SO2 is associated with respiratory problems, such as bronchitis, and can aggravate the symptoms of asthma and chronic lung disease. Column headings:...

DATA SOURCE: National Institute for Water and Atmospheric Research (NIWA) Adapted by Ministry for the Environment and Statistics New Zealand to provide for environmental reporting transparency Dataset used to develop the "Far fertiliser applied" indicator [available at https://statisticsnz.shinyapps.io/farm_fertiliser_applied_apr21/] ​ This indicator...

Bacteria and parasites are influenced by climate variables, and infection rates may increase in response to climate change and rising temperatures. Campylobacter, Cryptosporidium, and Salmonella are three such organisms that can contaminate our food and water, leading to serious illness. Monitoring the incidence rates of illnesses can help us assess the...

"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,...

Other human-made sources – such as aviation, forestry, and non-combustion industrial activities (eg grinding and crushing) – generally emit relatively small amounts of key air pollutants. Comparing their contribution to air pollution helps us understand the pressures they place on our air quality. Other human-made sources of air pollution include but are...

Marine non-indigenous (exotic) species arrive in New Zealand waters on the hulls of international vessels (biofouling) or in discharged ballast waters. Some have little impact or cannot survive in New Zealand waters; others have a negative impact on our native habitats and species and become pests. They can compete with, and prey on, indigenous species,...

A three-day rainfall measurement covers a single sustained rain event or a series of shorter events over a three-day period. Such measurements help us understand and prepare for flooding or rain-induced slips that could cause damage. Further information can be found in: Tait, A, Macara, G, & Paul, V. (2014) Preparation of climate datasets for the 2015...

"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,...

"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,...

The New Zealand River Environment Classification (REC) organises information about the physical characteristics of New Zealand's rivers. Individual river sections are mapped according to physical factors such as climate, source of flow for the river water, topography, and geology, and catchment land cover eg, forest, pasture or urban. Sections of river...

When nutrients accumulate in lakes (referred to as ‘nutrient enrichment’) above certain levels, they can make the lakes murky and green with algae, and lower oxygen levels. Lakes with extremely poor water quality are rarely suitable for recreation and provide poor habitats for aquatic species. Trends in the following parameters are provided: * Trophic...

Particulate matter 10 micrometres or less in diameter (PM10) in the air comprises solid particles and liquid droplets from both natural and human-made sources. PM10 is of particular concern because of high concentrations in some areas. It can also damage health, with associated effects ranging from respiratory irritation to cancer. This indicator...

Soil erosion reduces the productive capacity of land. Sediment entering waterways affects water quality, storage capacity, and biodiversity. Soil erosion in the North Island is primarily due to the historical clearance of forest on steep slopes for pastoral agriculture. South Island soil erosion is primarily due to high rainfall and steep mountainous...