Observing Our Ocean

Ocean observation is the foundation to everything we do within OCS. Our long term datasets enable us to provide information and advice for producing reliable models and recommendations. We regularly conduct our own surveys at sea and participate in international projects utilising the Marine Institute’s research infrastructure, including the Tom Crean and Celtic Explorer research vessels.


We observe and monitor Essential Ocean Variables (EOVs) in Irish waters, using research vessels, deep-water moorings, drifters and sea-gliders. In 2021 we published our Baseline Report (2021) detailing Ireland’s current EOV measurement programmes. The Baseline Report clarifies the significance of accurate and consistent measuring of EOVs to secure real-time support and services for ocean health and climate adaptation strategy for the government, policymakers, and public.


Essential Ocean Variables (EOVs)


  • Essential Ocean Variables (EOVs) are a collection of key physical, biological, biogeochemical, and ecosystem ocean measurements that are observed to inform policymaking, ocean resource management, and climate strategies. EOVs are a globally agreed upon subset of Essential Climate Variables (ECVs) outlined through the Global Climate Observing System (GCOS).
  • EOVs are crucial to our work at OCS. We monitor EOVs and produce tools and products to use the data that we and other researchers collect. OCS also produces recommendations in light of these observations and analyses. We have published our report on Irish Ocean Climate and Ecosystem Status Report for 2023 covering an analysis of EOVs in relation to Irish waters and ecosystems, the first update since our original 2009 report.



CTD Demonstration

Here you are viewing a CTD operations PC monitor which shows what you would expect to see when deploying a CTD (Conductivity, Temperature, with Depth) from the sea surface to the seabed. Where the GREEN line shows Dissolved Oxygen (DO) levels, RED shows temperature changes with depth, PINK shows denisty at depth and LIGHT BLUE represents salt concentrations as they change throughout the water column. Changes in these essential ocean variables help the scientists to find the depth location of different water mass types, e.g. salty warm water (with known values) at depth off the Irish west coast continental shelf can point to the presence of Mediterreanean Outflow Water that has travelled north from the Straits of Gibraltar.


View more of our processes aboard the Tom Crean below!