Title
|
New Zealand Ocean Acidification Observing Network (NZOA-ON) |
Date
|
2017-01-01T02:30:00 |
Date type
|
creation: date identifies when the resource was brought into existence
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Other citation details
|
The citation in a list of references is: "NZOA-ON [year-of-data-download], [Title], [data-access-url], accessed [date-of-access]"
|
Abstract
|
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.
|
Purpose
|
As the oceans take up carbon dioxide from the atmosphere, produced by burning fossil fuels, the waters are becoming more acidic.
Land practices, such as high nutrient run-off, can also impact the acidity of coastal waters. This will have implications
for marine ecosystems, particularly shell forming organisms such as kūtai, pāua, and tio, and early life stages of some
fish and shellfish. NIWA and the University of Otago have been measuring ocean carbon chemistry in the waters off Otago
since 1998. There is a lot of seasonal and interannual variability, however the long term trend is a gradual increase
in acidity, in line with what is being observed at other places around the world. However, we do not know much about other
New Zealand locations, particularly coastal regions.
|
Credit
|
NZOA-ON |
Status
|
onGoing: data is continually being updated
|
Descriptive keywords
|
Fixed station (theme). |
Thesaurus |
theme.aodn_aodn-platform-category-vocabulary_version-1-0.rdf |
|
Descriptive keywords
|
Global / Oceans | Pacific Ocean, Regional Seas | Tasman Sea, Countries | New Zealand (place). |
|
Descriptive keywords
|
|
Descriptive keywords
|
Physical-Water, Temperature, Salinity, Carbon, Alkalinity (theme). |
Thesaurus |
theme.aodn_aodn-parameter-category-vocabulary_version-1-1.rdf |
|
|
Language
|
English |
Character set
|
utf8: 8-bit variable size UCS Transfer Format, based on ISO/IEC 10646
|
Topic category code
|
oceans |
|
|
Minimum value
|
-5 |
Maximum value
|
0 |
|
Supplemental Information
|
New Zealand Ocean Acidification Observing Network (NZOA-ON) - discrete bottle data - 10 columns - -999 denotes a missing
value - Site sampling location - Date (NZST) yyyy-mm-ddThh:mm in NZST - T/oC measured at time of sampling, using a calibrated
thermistor - Salinity measured in sample bottle, using a YSI Pro-30 salinity meter - DIC concentration of Dissolved Inorganic
Carbon (micro mole per kilogram seawater) - AT alkalinity (micro mole per kilogram seawater) - pH at in situ temperature,
on total pH Scale, calculated from Alkalinity and DIC, using refitted Mehrbach constants - carbonate carbonate ion concentration
(micro mole per kilogram seawater), calculated from Alkalinity and DIC, using refitted Mehrbach constants - Omega(aragonite)
aragonite saturation, calculated from Alkalinity and DIC, using refitted Mehrbach constants - Omega(calcite) calcite saturation,
calculated from Alkalinity and DIC, using refitted Mehrbach constants
|
Sampling Frequency
|
fortnightly: data is updated every two weeks
|
|
|
Parameter Description
|
measured at time of sampling, using a calibrated thermistor |
|
|
|
Parameter Description
|
measured in sample bottle, using a YSI Pro-30 salinity meter |
|
|
|
|
|
|
|
|
|
|