Ocean acidification conditions around the New Zealand coast are being measured to establish baseline conditions and to quantify future change. The NZOA-ON is a network of coastal sites around the country – a mix of pristine and urban sites, and sites which are of particular interest to regional councils, the aquaculture and fishing industries, and sites of scientific interest. Data will be used to determine local conditions, and to provide a baseline against which to measure future change. This network is linked into the Global Ocean Acidification Observing Network (GOA-ON The network uses existing data collection infrastructure where possible to take advantage of auxiliary data and historic records. Sampling partners collect fortnightly water samples, liaise regarding shipment and logistics, and assist with deployment of the sensors. Sampling partners collecting the water samples, possibly as part of existing monitoring programmes, have access to the data to help them with their own management strategies. Sampling partners include regional councils, the Department of Conservation, and aquaculture industries. Water samples are taken fortnightly at each site (see Figure 1 for the sampling sites) by the sampling partners, then the full crates are returned to Dunedin for analysis of acidity parameters - alkalinity and total dissolved inorganic carbon (to develop a long-term data series). We then calculate pHT, pCO2, carbonate ion concentration, and saturation states. NIWA provides sampling partners with bottles, crates, chemically resistant gloves and training (including health and safety information). The actual sampling isn’t difficult, however sampling partners are required to use a droplet bottle to add a couple of drops of mercuric chloride (which is toxic) into the full sample bottles, so that the seawater is ‘preserved’ until it gets to the lab. SeaFET pH sensors[2] are deployed for 4-5 months at each site, and are moved from site to site to help determine short term variability at each location. Additional parameters are measured at the Dunedin and Firth of Thames sites, so that these sites meet the extra requirements of the Global Ocean Acidification Observing Network (GOA-ON). The network uses data collection infrastructure where possible to take advantage of auxiliary data and historic records.

Gravel percentage of seafloor sediments from the New Zealand region from nzSEABED database. Data or descriptions of gravel content are from the top 10 cm of the seafloor. Gravel is defined by its texture/grainsize (all sediment <2mm) and does not reflect the composition of the seafloor sediment.

Using seafloor image data to build single-taxon and community distribution models for seabed fauna in New Zealand waters. Understanding the spatial distributions of seabed biodiversity is essential for effective management of the effects of human activities including fishing and mining. To improve understanding of seabed fauna distributions, we are developing a new database of benthic invertebrate occurrences in New Zealand waters by assembling quantitative data from all available seabed photographic surveys. By modelling the spatial relationships between taxon occurrences and environmental gradients across the region, we are able to predict the likelihood of individual taxa and communities being present in as-yet unsampled areas. In the first phase of the project, we concentrated on Chatham Rise; a region of high importance to commercial fisheries and with the highest density of available seabed imagery. Predictions from the models developed here are the first abundance-based models of benthic distributions in the New Zealand region and are the best-informed representations of seabed distributions on Chatham Rise to date, providing a resource that will have applications in marine environmental management and ecosystem research. All rasters are in a geotiff format at a 1000 m resolution cell size and projected to WGS 84 / Mercator 41 - EPSG:3994 coordinate system.

This data collection contains water column observations from CTD probes and water bottles deployed by the National Institute of Water and Atmospheric Research (NIWA) and its predecessor, the New Zealand Oceanographic Institute. A variety of instruments where used in this dataset, including: Sea-Bird SBE 911Plus CTD

Carbonate percentage of seafloor sediments from the New Zealand region from nzSEABED database. Data or descriptions of carbonate content are from the top 10 cm of the seafloor. The carbonate % represents the contribution of sediment produced by marine organisms (e.g. shells, skeletons). The converse (non-carbonate %) thus represents the contribution of sediment from the land (terrestrial sediment) transported to the marine environment primarily via rivers. The exception to this is that some regions there is also a significant contribution of authigenic minerals (minerals such as glauconite that are formed in the marine environment under specific conditions).

New Zealand is not immune to ocean acidification. The ‘Munida transect’ Time-series in sub-antarctic waters off Otago is the Southern Hemisphere’s longest-running record of pH measurements. Monitoring since 1998 has established a decline in pH that reflects the increase in atmospheric CO2 recorded at NIWA’s atmospheric research station near Wellington. The Munida time-series is led by NIWA’s Kim Currie, in collaboration with the University of Otago's Department of Chemistry. Every two months she has collected water samples along a 65-kilometre line from the tip of Otago Harbour out to sub-antarctic waters. This time-series is particularly valuable because it covers both subtropical and sub-antarctic waters in a one-day trip, so is in a unique location. During the transect University of Otago scientists measure the pH while Currie measures alkalinity, total dissolved inorganic carbon and CO2 as well as other related parameters. The supporting data help to determine what processes are causing changes in the properties of the water masses, including the changes in pH. For example, pH is linked to temperature and therefore varies between summer and winter and also year to year. Parameters in the data set include: XCO2_DRY - Mole fraction of carbon dioxide (dry air) in the headspace of the equilibrator, unit micromole / mole XH2O - Mole fraction of water vapour (dry air) in the headspace of the equilibrator, unit micromole / mole EQ_PRE - The pressure in the equilibrator head space in hectopascal EQ_TEMP - The temperature of the water in the equilibrator PCO2_WAT - The Partial pressure of carbon dioxide in the water body in units of microatmospheres

This data collection contains observations from CTD sensors attached fisheries trawls deployed by the National Institute of Water and Atmospheric Research (NIWA) and funded by the Ministry of Primary Industries. Data was sourced from SeaBird MircoCAT SBE 37 instruments which were attached to the headlines of trawl nets as part of fisheries research programs. The data is processed using the SBE Data Processing software and only the downcast of the cast is retained (because of the turbulence of the water generated by the trawl gear once the trawl is underway. Measured variables are temperature, depth, and salinity. The sensors on the CTD are all regularly calibrated by the manufacturer, but data are not calibrated in-situ.

From 1997 to 2008, a research programme to determine if fish assemblages in the New Zealand region could be classified into clearly identifiable communities based on their associations with each other and with environmental features was undertaken. The programme resulted in the creation of the Fish Communities Database, from which this dataset was extracted. The data set includes records from 1964 to 2008. These data have been used to show geographical and depth distributions of species from all research tows within the New Zealand EEZ since 2008. The main source of data was the Ministry for Primary Industries research trawl database.

This dataset is part of the IMOS Underway CO2 Measurements group. This group is a research and data collection project working within the IMOS Ship of Opportunity Multi-Disciplinary Underway Network sub-facility. The CO2 group sample critical regions of the Southern Ocean, Australian and the New Zealand shelf waters, which have a major impact on CO2 uptake by the ocean. These are regions where biogeochemical cycling is predicted to be particularly sensitive to a changing climate. The pCO2 Underway System measures the fugacity of carbon dioxide (fCO2) along with other variables such as sea surface salinity (SSS) and sea surface temperature (SST) using an automated system. The RV Tangaroa provides data on surface ocean CO2 for the oceans adjacent to New Zealand.

Using seafloor image data to build single-taxon and community distribution models for seabed fauna in New Zealand waters. Understanding the spatial distributions of seabed biodiversity is essential for effective management of the effects of human activities. However, existing knowledge of seabed faunal distributions comes overwhelmingly from records of museum specimens and fisheries and research trawl bycatch. Data from such sources have been used to build models that predict species and community distributions on the basis of correlations with environmental gradients but because these models are based on presence-only data from disparate sources and times, their predictions are considered uncertain. To improve understanding of seabed fauna distributions around New Zealand, we are developing a new database of occurrences and population densities based entirely on quantitative data from seabed photographic surveys designed to sample these fauna. By modelling the spatial relationships between taxon occurrences and environmental gradients across the region, we are able to predict the likelihood of individual taxa and communities being present in as-yet unsampled areas. In the first phase of the project, we concentrated on Chatham Rise; a region of high importance to commercial fisheries and with the highest density of existing seabed imagery. The models developed here were the first abundance-based models of benthic distributions in the New Zealand region at these spatial scales. In the second phase, we expanded the domain of the predictive models to encompass Campbell Plateau, in the south-eastern sector the EEZ. Combining data from Chatham Rise and Campbell Plateau in a single dataset of benthic invertebrate taxon occurrences and population densities enabled development of up-dated predictive distribution models for a range of individual invertebrate taxa, as well as models of the spatial variability in overall community composition. Rasters are in a geotiff format at a 1000 m resolution cell size and have their relevant projections written in their files.