This project deploys O₂ and pH sensors as an add-on component to the other planned Alaska field projects and on bottom trawl surveys of the Gulf of Alaska (FY13) and Aleutian Islands (FY12 and FY14). This will allow a region-wide collection of data during the summer months hopefully collecting up to 800 deployments of pH and O₂ data per year from Dixon Entrance in SE Alaska to Stalemate Bank in the far-western Aleutian Islands. These data will be incorporated into the Coral and Sponge Distribution Model Validation Fieldwork conducted in FY12-14 and will be compared to information on coral and sponge health collected in the Gulf of Alaska HAPC Study.

The effects of global climate change and ocean acidification loom large in Alaska. These environmental changes are expected to have larger impacts at high latitudes, and in fact many effects of climate change are already being observed in Alaska. Deep-coral and sponge ecosystems are especially susceptible to ocean acidification through reductions in calcification rates due to reduction in the available carbonate ions. Deep corals in other systems have also been found to be more abundant at O₂ minimum zones than in other areas (although this phenomenon has not been explained. Thus it is important to determine the rates of ocean acidification through monitoring pH and to determine changes in the distribution of the O₂ minimum zones in order to predict and understand the effects of climate change on deep coral and sponge ecosystems.

In FY12-14 we will purchase and deploy O₂ and pH sensors built by Aanderaa Data Instruments.  These sensors will be deployed as an add-on component to the other planned Alaska field projects (i.e. each field project in Alaska will have access to and be expected to collect pH and O₂ data during their study). In addition, units will be purchased to deploy on bottom trawl surveys of the Gulf of Alaska (FY13) and Aleutian Islands (FY12 and FY14). This will allow a region-wide collection of data during the summer months hopefully collecting up to 800 deployments of pH and O₂ data per year from Dixon Entrance in SE Alaska to Stalemate Bank in the far-western Aleutian Islands. These data will be incorporated into the Coral and Sponge Distribution Model Validation Fieldwork conducted in FY12-14 and will be compared to information on coral and sponge health collected in the Gulf of Alaska HAPC Study. In addition, the sensors will continue to be deployed on the bottom trawl surveys after the conclusion of the Alaska Region Fieldwork Initiative (FY15 and beyond) and will be integrated into the time series of environmental data available from these surveys.