CO2 in the Ocean and Ocean Acidification (NIWA Core Funding)

This project aims to characterise the carbonate chemistry in New Zealand coastal regions and the waters of the South Pacific, including spatial and temporal variations, and the underlying mechanisms driving the observed variability.

As part of this approach we have been looking at the CO2 chemistry of the waters off the coast of Otago since 1998 (Kim Currie, Keith Hunter, Malcolm Reid), using a time series approach. Over the past 14 years careful measurements of CO2 species and other related parameters have been made to try and understand the changes that occur in these waters – seasonally, from year to year, and over the long- term.

Ocean Acidification is a consequence of the oceans taking up anthropogenic carbon dioxide from the atmosphere – the pH of the seawater decreases and the carbonate ion concentration also decreases, with impacts on many marine species and ecosystems. The rate and magnitude of coastal ocean acidification is monitored at many sites throughout New Zealand by the NZOA-ON (New Zealand Ocean Acidification Observing Network), in collaboration with sampling partners from Regional Councils, the aquaculture and fishing industries, research institutes and DoC (Kim Currie, Keith Hunter).