By Nick Morrison
Carried along by the Gulf Stream
Prof Peter Wadhams and Martin Gray gave a fascinating talk on the origins and effects of the Gulf Stream and what it brings to Orkney’s shores.
There are 2 components of the Gulf Stream the main and biggest is the wind driven component bringing warm surface waters (up to 30 Deg C) from the Gulf of Mexico up the eastern seaboard of North America and then east across the North Atlantic where it spits into smaller streams.
Fortunately for us one of these smaller streams more or less runs into Orkney. The other streams bathe most of Northern Europe, the consequence of this is that most of Northern Europe is some 10 Deg C warmer than it should be given its latitude. For example Edinburgh is the same latitude as Moscow. The relative winter warmth of Edinburgh is down to the Gulf Stream.
The other component of the Gulf stream is the thermohaline stream. As the surface of the sea in the Arctic freezes it forms relatively freshwater ice increasing the salinity sea underneath it. This cooler more saline water sinks and flows southwards to the Gulf of Mexico. Well that’s the simplified version!
Our own Martin Gray took over from Prof Wadhams and showed us some examples of what is carried by the Gulf Stream to Orkney shores. These included coconuts, “sea beans” some of which are still viable when they get here, hard wood branches, exotic shells, and pumice from Iceland.
The Naval wrecks of Scapa Flow.
Dr Joanne Porter gave lecture on recent surveys of the remains of the German Fleet scuttled in 1919, The Royal Oak, Hampshire and Vanguard. As part of a multi disciplinary project for Historic Environment Scotland and Marine Scotland. The MOD only gave permission for the pics to be shown to the public that very afternoon. We saw pics of derricks and gun turrets and debris fields from the German fleet. The whole of the Royal Oak is colonized by various forms of marine life. Like seaweeds, algae, molluscs and jellyfish. Unfortunately my tablet lacks sufficient discrimination to bring you pics of these.
Related Story: Marine Archaeologists on the sunken German High Seas Fleet
Science at the Sea School
Mark Shiner gave a one man “Family Day” at the Sea School. It trains fishermen and merchant marine crews in sea safety amongst many other maritime activities. He introduced the concepts of buoyancy/flotation/ center of gravity with the aid of models, some of which we made and Ferry practices which most Islanders have experienced without actually appreciating what was happening at the time:namely a shortish delay between the finish of loading and setting off. What is happening is that the ship’s crew are pumping ballast water around to make the ship ride level if a heavy lorry has come in at one end or one side of the ship. So now we know!
He also told as about various knots and there uses. At one time he stood there with a rope twixt thumb and forefinger whilst 2 young boys failed to pull him over. A simple round turn twas the secret. Excellent family day.