An acidification mooring with a CO2 sensor was first deployed at Maria Island NRS in April 2011. Every 6 months the mooring is swapped out to avoid biofouling affecting data quality. Data are transmitted daily from the mooring and available in the Ocean Portal. A pH sensor was also deployed on the Maria Island mooring in April 2012.
A second acidification mooring was deployed at the Kangaroo Island NRS in February 2012. The site is subjected to frequent high seas, strong winds and variable currents and the mooring design, has withstood major storms and high seas. The mooring is turned around at approximately six month intervals.
A third acidification sensor was deployed on a large IMOS mooring at the Yongala NRS in late 2010. This was a different surface buoy and mooring design than used at the other sites. The surface buoy and instruments were damaged by Cyclone Yasi shortly after deployment. An assessment of the mooring data found the anchoring system was too rigid and this caused problems with the CO2 equilibration chamber due to waves washing over the mooring rather than the mooring riding up and down with the water level. The mooring buoy was redeployed in September 2013 and to offset the issues with the anchoring system the equilibration. This mooring damaged by another cyclone in early 2014 and the mapCO2 system flooded with seawater when a piece of the mooring structure broke the top off a sealed pod of the mapCO2 system . The Yongala mooring was deployed and maintained by the Australian Institute of Marine Science, and due to problems with the original mooring design has recently been replaced with a smaller mooring. The new mooring design cannot hold the CO2 instrumentation, and in early 2015 a decision was made to move the mooring instrumentation to Heron Island. This was deployed successfully and is working well. It uses the same style of mooring as the Maria and Kangaroo Island sites and is able to withstand more extreme weather than the Yongala designs.