MiTHO project participant Dr Victor Martinez-Vicente led the activities for the week, with a focus on introducing students to the use of ocean colour measured from satellites and how it is (in practice) related to the properties of water constituents.
The Plymouth coastal water was simulated with a 1000 litre tank, filled with water and sediments from the Plymouth Sound sea floor in the UK.
In this gallery of photos, you can see an experiment from the week where they simulated coastal water and their own “satellite”.
The “satellite” was a hyperspectral radiometer, which follows similar measurement principles to the real satellites under construction by the European Space Agency, ESA. They added different amounts of sediment to increase the turbidity (the relative clarity or cloudiness) of the water and measured the increased turbidity using the “model satellite”.
In the experiment, they also used measurements that anyone can use – citizen science tools – useful for monitoring the coast where satellites have blind spots (e.g. very close to land).
The students took high-tech citizen science smartphone camera measurements through the HydroColor App – which uses a phone’s digital camera to determine the reflectance of natural water bodies and also measurements with very ancient tools, such as the Secchi Disk.
A Secchi disk, historically called a “dinner plate” by sailors, is a simple water quality monitoring tool that has been used since the mid 19th Century. Secchi disks are used in the open ocean to measure water turbidity, they work by lowering the white disk into the water and recording the depth at which it disappears, and this tool is still useful to ocean scientists today, even in the age of satellites.
The work links with the work of the MiTHO project but also the ESA-funded HyperBOOST projects, which involve monitoring marine ecosystem health and threats by using in-situ hyperspectral bio-optical and satellite measurements.
