Born: November 15, 1926; Died: November 4, 2013.
John Steele, who has died aged 86, was a globally-renowned Edinburgh-born oceanographer. He presided over the American underwater research team which, in a joint operation with their French counterparts, discovered the wreck of the Titanic on the Atlantic seabed on September 1, 1985, 73 years after she hit an iceberg and sank.
After emigrating to the US when he was 30, he also used his earlier research in the North Sea off Aberdeen and on Loch Ewe, a sea loch in the north-western Highlands, to develop international projects which investigated the role of the oceans in climate change.
Having first gained a degree in mathematics from University College, London, he developed a method which applied mathematical calculations to the scientific study of marine ecosystems.
The mathematical tools he developed have become central to fisheries management and predicting how oceans might affect climate change.
His ground-breaking 1974 book The Structure of Marine Ecosystems, which laid out his methods, has been described as the oceanographer's bible.
Having taken US citizenship, Dr Steele spent most of his career at the Woods Hole Oceanographic Institution (WHOI) in Massachusetts, a private, non-profit facility for the study of marine science and the education of marine researchers.
The village of Woods Hole, in the extreme south-west corner of Cape Cod near Martha's Vineyard, is part of Falmouth, where he would spent the rest of his life and where he died at home.
He was director of the WHOI from 1977-89 which include those days in 1985 when the Institution hit world headlines over the discovery of the Titanic at the bottom of the North Atlantic.
Although he was not personally on the mission, Dr Steele, as WHOI director, was in charge of the Institution's team of marine researchers, led by former US Navy officer Robert Ballard, who joined forces with French oceanographers to find the ill-fated liner.
Ballard and his counterpart Jean-Louis Michel of the French Research Institute for Exploitation of the Sea (IFREMER), finally located the Titanic more than 13 miles from the position transmitted by its crew while it was sinking.
"Finding the Titanic is a dramatic demonstration of our present capability to explore the ocean depths for scientific purposes," Dr Steele said at the time.
"It has taken years of work by dedicated engineers and will prove its value to science and the nation in the years ahead."
However, colleagues said although he realised finding the Titanic would be of immense benefit to oceanography, he was uncomfortable with the media glitz over the discovery and was happy to get back to his roots studying marine ecosystems, how they were changing and how they could be protected.
John Hyslop Steele was born in Edinburgh on November 15, 1926. He attended the city's George Watson's College before moving south to gain a degree in mathematics at University College, London, where he would later be awarded a Doctorate of Sciences (DSc).
For his post-war national service, he worked as a specialist in aeronautical mechanics in the Royal Aircraft Establishment (RAE), first in Helensburgh on the Clyde estuary and later down south at Thurleigh and Bedford. But it was the sea not the sky which would become his passion.
He once said he had chosen a career in marine research largely because "I wanted to spend more time messing about in boats". After the war, he enjoyed sailing to and from France across the Channel with friends, often wondering what lay beneath as the debris of war.
In 1951, he got a job in fisheries' management with the Marine Laboratory in Aberdeen, now part of Marine Scotland and spread among Aberdeen, Edinburgh, Pitlochry and elsewhere. It was while in Aberdeen that he realised fisheries management required a broader knowledge of the oceans.
Using his training in maths, he began, along with a London-born colleague Val (Valentine) Worthington, measuring ocean currents and later the lives of the microscopic plants and animals in the marine food chain.
Much of his research was carried out at Fladen Ground, between Scotland and Norway, where he analysed nutrient supplies, plant growth and animal production in an area rich in oil and natural gas but still good fishing for such species as Norway Lobster.
Shifting his emphasis to the west coast of Scotland in Loch Ewe, Wester Ross, Dr Steele took measurements using devices known as mesocosms - large, open floating bags - to study the marine environment under controlled conditions as a template for wider phenomena.
"John Steele was indeed a giant in our field," said John Cullen, a professor of oceanography at Dalhousie University in Halifax, Nova Scotia. "He established the foundations of modern oceanographic research that routinely uses simulation models to examine how the ocean responds to climate change, fisheries pressure, and the like."
After retiring from the WHOI in 1989, Dr Steele remained highly active in his field, continuing private research and serving on the boards of several organisations including an increasingly-repentant Exxon Co-operation as a marine environment expert.
He and his wife Evelyn, whom he married in 1956, were famed for their hospitality in Falmouth and enjoyed sailing around Cape Cod. They also returned regularly to Scotland, where they retained a cottage near Aberdeen, and always passed through Henley-on-Thames to sail the river with their son Hugh, daughter-in-law Jenny and grandsons Adam and Owen. The family, in turn, spent summer holidays in the Woods Hole area.
Dr Steele died of cancer in his home in Falmouth, Massachusetts.
He is survived by his wife of 57 years, Evelyn, their son Hugh, daughter-in-law Jenny and grandsons Adam and Owen (all of Henley-on-Thames).