Ocean drifters off Shetland tackle climate change

SEVEN ocean drifters equipped with satellite trackers have been released off the west of Shetland in an attempt to chart currents and tackle global climate change.

The floating devices released as part of the latest Marine Scotland Science research programme provide hourly positions and allow scientists to study ocean currents in greater detail.

Although the study is in its early stages, interesting patterns of how water flows around the Northern Isles are already being observed.

Ocean drifters have been used by scientists for more than a century with examples of earlier technology, including glass bottles and plastic markers, still being found on Scotland’s shores.

A plastic ocean drifter found on a beach in Edinburgh in May this year was found to have been released in 1969 as part of a detailed study of circulation patterns in the Firth of Forth.

Environment minister Aileen McLeod said: “Marine Scotland continually uses drifters to study ocean currents in Scottish seas and coastal areas.

“Over the years these drifters have undertaken extraordinary journeys and we’re beginning to understand more about how currents work.

“With developments in technology, these drifters now play an important role in discovering the secrets of the seas and helping us to understand our environment and the effects of climate change.”

The drifters were previously used in a collaborative project in 2013 to develop new observational models to help in the clean-up of oil spills.

This study, led by Qualitas Remos Ltd and Marine Scotland, used high-frequency radar technology to give live information about the speed and direction of Scotland’s surface currents.

Dr Bee Berx, from Marine Scotland Science, said: “The satellite-tracked drifters are showing us in great detail the transport pathways of our coastal currents.

“Our next challenge is to interpret these results, to improve our understanding of circulation in the region and to incorporate this new knowledge in our advice.”

Using the same tracking technology, an education outreach project in the US launched a number of unmanned sailboats last year, one of which arrived at Papa Westray in Orkney in April.

During the 1969 study, scientists released a total of 2,000 markers over the course of the year and at different stages of the tide to study variations in tidal and seasonal currents in the Forth.

Earlier this year, in a similar project, the Scottish Association for Marine Science released an update on seven underwater robots that have travelled thousands of miles to help scientists gain a better understanding of climate change.

The seven Seagliders, all named after different brands of Scottish whisky, are 6ft long and collect data such as temperature, salinity, pressure and oxygen levels.

The machines, which are controlled by scientists in Oban, have travelled a total distance of more than 20,000 miles in five years, reaching as far as Iceland.

Just last week, one of the Seagliders broke a distance record by completing a return journey of more than 2,100 miles along what oceanographers call the “Extended Ellett Line” – a route from Scotland to Iceland that has been surveyed by scientists for 40 years.