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A large-scale view of ocean conditions
Satellite observations provide consistent environmental information over broad areas. The resulting datasets support day-to-day decision-making, long-term planning, and public understanding of marine environments.
Tracking Ocean Temperature
- monitor seasonal and long-term temperature trends
- detect temperature anomalies linked to climate change
- identify and track marine heatwaves, including their duration and intensity
Understanding Marine Heatwaves
- stress on marine species and ecosystems
- increased risk of disease and harmful outbreaks
- disruption to coastal and marine-based activities
Ocean Colour and Ecosystem Health
- changes in phytoplankton activity at the ocean surface
- the development and extent of blooms
- primary production and ecosystem productivity
- variations in water quality
Supporting Decisions and Insights
- support evidence-based marine management and policy development
- inform planning, operations, and risk assessment in marine sectors
- enhance climate monitoring and reporting
- communicate complex ocean data in a clear and accessible way
Explore Remote Sensing Products
View sea-temperature, marine-heatwave, and chlorophyll products for Irish waters.
Sea Surface Temperature
View sea surface temperature across the Irish Exclusive Economic Zone for the latest two-week period. The data come from the Operational Sea Surface Temperature and Ice Analysis system run by the UK's Met Office and delivered by IFREMER.
Sea Surface Temperature Anomaly
Compare sea surface temperature from the latest two-week period with the 1993-2022 OSTIA reference baseline climatology.
Marine Heat Waves
View active marine-heatwave intensity as a sea surface temperature anomaly calculated against the 1993-2022 OSTIA reference baseline climatology.
Surface Temperature Historical
Select a site on the map to view historical sea surface temperature from 1982 to the present, using Operational Sea Surface Temperature and Ice Analysis data.
Chlorophyll-a Concentration
Compare chlorophyll-a mass concentration in seawater with an anomaly calculated from a 60-day running median ending two weeks before the current image. Data include Atlantic Ocean Colour Bio-Geo-Chemical L4 Satellite Observations.
Red Band Difference Algorithm
Explore a satellite-derived indicator of relative chlorophyll-a fluorescence for identifying potential bloom concentrations in open and coastal waters.
How the Red Band Difference Algorithm Works
The Red Band Difference (RBD) algorithm calculates the difference between two red bands as a proxy for relative chlorophyll-a fluorescence. Amin et al. (2009) described the method, and Jordan et al. (2021) tested it in Irish waters.
The algorithm is less sensitive to coloured dissolved organic matter, suspended particulate matter, and atmospheric corrections. This makes it useful in both open and coastal waters.
Warmer colours indicate higher relative fluorescence and potential bloom concentration. Grey represents clouds or other invalid data. Black indicates no bloom detection or may represent several cloudy days in the area.
The images use Copernicus Sentinel-3A and Sentinel-3B satellite data from the European Organisation for the Exploitation of Meteorological Satellites. NOAA's National Centers for Coastal Ocean Science processes the daily imagery.
View the related chlorophyll-a product.
References
- Amin R, Zhou J, Gilerson A, Gross B, Moshary F, and Ahmed S (2009). Novel optical techniques for detecting and classifying toxic dinoflagellate Karenia brevis blooms using satellite imagery. Opt. Express 17, 9126–9144. doi: 10.1364/oe.17.009126
- Jordan C, Cusack C, Tomlinson MC, Meredith A, McGeady R, Salas R, et al. (2021). Using the red band difference algorithm to detect and monitor a Karenia spp. bloom off the south coast of Ireland, June 2019. Front. Mar. Sci. 8:638889. doi: 10.3389/fmars.2021.638889