(Shell)Eye in the sky
23 October 2015
Dr Hayley Evers-King (ShellEye scientist from Plymouth Marine Laboratory) gives an account of working with satellites to study the ocean...
We’ve probably all been captivated by pictures taken from above. Whether the view from a plane window, photos from the international space station or just the view over a city from a tall building, there’s something inherently awe-inspiring about getting this perspective. As well as being fascinating, images from above can provide huge amounts of information. Through the use of images from satellites in space, the ShellEye project hopes to gather useful information about the environments in which aquaculture takes place.
It is an exciting time to be working with satellite images to study oceans, coasts and inland waters. Landsat 8, the recently launched Sentinel 2, and soon to be launched Sentinel 3, are all satellites which carry instruments to capture images of our coastal environments with high levels of detail. This new technology, and freely available environmental data, opens up many opportunities for scientists and businesses to develop new ways to cope with marine-related challenges and identify opportunities.
The science behind the satellite imagery revolves around colour. Instruments aboard these satellites quantify what we intuitively see and understand with our eyes, but in greater detail. How green the water is can be related to the amount of algae present; the main source of food at the base of ocean food webs. Looking at other parts of the colour spectrum can indicate the presence of certain types of harmful algae. Similarly, river plumes can be identified, their extent mapped, and their behaviour in the wider coastal environment understood.
During the ShellEye project so far, scientists have been working on assessing the different types of satellite data available for waters around the UK. Data availability can be influenced by cloud cover, and the frequency of images acquired can vary depending on which satellite is being used. By looking at multiple sources of satellite data, the amount of useful data available can be maximised.
There is a substantial archive of historical data to be looked at and this is being used to test methods, understand typical features of coastal regions, and identify events and changes. This work is also being done with a view to use the new Sentinel satellites, being launched by the European Space Agency over the next few years, ensuring that these sorts of methods have a long-term future.
As the project progresses, ShellEye scientists will be linking satellite images with environmental data collected, with help from project partners, and exploring how these new technologies and huge amounts of data can be used for the benefit of the aquaculture industry.