Many environments, many pH regimes: the first year of the New Zealand ocean acidification Observing Network

Chair: Kumiko Azetsu-Scott

Kim Currie (1)*, Judith Murdoch (2), Andrew Marriner (3)

1 NIWA, Dunedin, New Zealand,
2 University of Otago, Dunedin, New Zealand
3 NIWA, Wellington, New Zealand

Background
Long–term monitoring of ocean carbon chemistry in the surface waters of the SW Pacific Ocean near New Zealand (the Munida time series) has shown that the pHT has decreased at a rate of 0.0013 pH units per year for the period 1998-2012 (Bates et al, 2014).

Methods
The New Zealand coastal ocean acidification observing network (NZOA-ON) consists of 11 sites around the country, in partnership with aquaculture industry representatives, regional councils, conservation and other institutes. Fortnightly bottle samples for DIC and alkalinity analyses are collected, plus SeaFET pH sensors collect data every 30 minutes at sites, on a roving basis.

Conclusions
The first year of data confirms the spatial variability around the New Zealand coast, and provides a base-line against which to measure future change in each of the different coastal environments.

Reference
Bates, N.R., et al. Oceanography 27 (1), 126-141.