With parents who were fond of music, and with four lively younger brothers, his early days in the family home at Ackergill, Kelty, were happy ones. He was within walking distance of Blairadam, Ben Arty and Loch Leven, and he soon developed a great love of unspoiled nature. Throughout his life he enjoyed camping in Glen Feshie, walking and climbing in the Scottish mountains, and above all the cultivation of his beautiful garden at Abernethy in Perthshire.
In 1921 he came from Beath Secondary School to Edinburgh University to study forestry at a time when there were ample prospects of a career as a Forestry Officer in the Colonial Service. In his first university year he won the Medal in Natural Philosophy, and was persuaded to study for an honours M.A. in Mathematics and Natural Philosophy. On completing this degree he took also a First Class honours B.Sc. in Physics. After spending a year in the Meteorological Office in London he accepted in 1928 a Lectureship in Natural Philosophy at Edinburgh University, where his ability as a teacher was quickly recognised and greatly appreciated by the students. Under Professor Barkla's direction he spent some unprofitable years in a search for the hypothetical J-phenomenon, and then had to find a research field of his own.
In the meantime he had maintained his interest in meteorology, having become an R.A.F. Reserve Met. Officer and a member of the Scottish Branch of the Meteorological Society. At the close of the 1932-33 Second International Polar Year, James Stagg, who had led the British Expedition to Fort Rae in the Canadian sub-Arctic, returned to the Edinburgh Meteorological Office, and in 1934, invited Mr Paton to assist him with the analysis of the Fort Rae recordings - an invitation that was gladly accepted. The records included continuous recordings giving the components of magnetic field, and some 900 pairs of auroral photographs - simultaneous pairs taken from two stations, 25 km apart and linked by telephone. The parallax shown by the pairs of photographs against the star background gave the height of the aurora. Mr Paton's assistance proved fruitful for the immediate task, especially in explaining the connection between certain changes of magnetic field and the movement of quiet auroral arcs, but it was still more fruitful in determining the direction of his future research. He became deeply interested in upper-atmosphere phenomena; he saw clearly the need for more work in this field, and the value of visual observation by the dark-adapted eye of transient auroral features which could not be recorded by a camera. In 1938 he began visual study of aurora and parallactic photography on a two-station base-line. There were, however, obstacles to the progress of the research.
During the 1930's Mr Paton's health gave increasing cause for anxiety. In 1940 he resigned on grounds of health from the R.A.F. Reserve - with the retention of the rank of Flying Officer, and for the rest of his life had to follow a restricted diet which, in later years, made attendance at foreign conferences difficult for him. The outbreak of World War II brought research to an end. Mr Paton's teaching commitments became heavier and included courses in meteorology for R.A.F. pilots and navigating officers. When the war ended, this teaching experience formed the basis of an undergraduate course in meteorology of seventy-five lectures and fifty hours of tutorial and practical work which began in 1945, and was the first such course to be given at a British university. A short course at honours level was also instituted. Mr Paton was promoted to Senior Lecturer in 1950, to Reader in 1954 and to Head of an independent Department of Meteorology in 1964.
As soon as the war was over he began to organise a four-station network for parallactic auroral photography. The provision of special telephone services in 1945 under difficult post-war conditions was assisted by Sir Edward Appleton, himself an upper-atmosphere physicist. The network, free of the fog and lights of a city, was operated from Abernethy, with Mr Thomson at Newburgh (Fife), Mr McKellican at Blairgowrie and Mr Geddie (and later Mr Wilson) at Newton Stewart. This was the beginning of Mr Paton's long and successful experience of collaboration with amateur observers. Routine photography of aurora began in 1947 and photography of noctilucent clouds (NLC) was included after one of these was seen at Abernethy in 1949. The self-luminous aurora (located in the ionosphere) were rare occurrences at Abernethy, and were known to be associated with sun spots. The NLC (located in the low-temperature mesopause) were still rarer occurrences, seen only in summer and only when illuminated by sunlight against a dark sky; during the previous sixty years they had been reported at intervals of many years by a few observers in the northern hemisphere, and their nature was uncertain. In Mr Paton's characteristic words 'a careful watch was kept' on nights when there was good star visibility. The watch became easier after he built a small observatory in the roof of his house, in time for the opening of the International Geophysical Year (IGY) 1957-58. Another period of intense activity was associated with the International Year of the Quiet Sun (IQSY) 1964-65; over a period of two months in the summer of 1964, NLC were seen at Abernethy on twenty nights. Since these clouds revealed the behaviour of the atmosphere at a height of about 80 km, and the illuminated region of the mesopause moved southwards during the night, the clouds were studied throughout their period of visibility-sometimes for four or five hours. Mr Paton's indefatigable study made him internationally a leading expert on NLC.
In 1952 Mr Paton became Director of the British Astronomical Association's Aurora Section, which had about fifty members, mostly amateur observers. He prepared notes for their guidance and printed forms for their observations of aurora and NLC. In 1954, in preparation for the IGY, he was asked to serve as British National Reporter for Visual Aurora. Since a continuous night watch would be necessary during the IGY, he made arrangements to supplement the Aurora Section with professional people who were on duty at night. Approaches were made through Directors of Meteorological Services, civil air lines, military air forces, and shipping lines, and in these and other ways, he formed a very large and useful group to provide reports, not only from the British Isles but also from the Atlantic, Greenland, Iceland, the Faroes and countries in western Europe. By 1956 Edinburgh had become the obvious choice as one of the three World Data Centres for the IGY, the other two Centres being at Cornell (U.S.A.) and lzmiran (U.S.S.R.). Mr Paton was involved in drafting parts of the IGY Instruction Manual and, for his Region, was responsible for the design and production of an observer's alidade, the distribution of instruments and report forms, and for the programme and interpretation of photographs taken with the all-sky cameras at Halley Bay and in Scotland. The World Data Centres continued in operation after the close of the IGY and served also for the IQSY. Thereafter the meteorological interest of the NLC was widely recognised and, as from 1969, the reporting of NLC has come under the direction of the World Meteorological Organisation, with World Data Centres at Edinburgh, Toronto and Tartu (Estonia). Under Mr Paton's direction Edinburgh has therefore served as a Data Centre over a period of sixteen years, for both aurora and NLC. The data stored in the Balfour Stewart Auroral Laboratory are made available to research workers from any country.
The organisation of the IGY and the IQSY involved careful preparation by committees to ensure that the procedures and data reporting would be internationally uniform. From 1950 till his death, Mr Paton was a member of two Sub-Committees of the British National Committee for Geodesy and Geophysics. He was a member of the British National Committees for the IGY (1952-59), for Co-operation in Geophysics (1960-67) and for the IQSY (1962-67), and attended as Royal Society Delegate the Special IGY Committee Meeting in Moscow. For the International Association of Geodesy and Aeronomy, he served on the Aurora and Airglow Committee (1960-63) and its continuation as Commission VI (1963-67), and was Chairman of a Special Committee set up at the Helsinki meeting in 1960 to revise the classification of auroral forms and to produce a new Auroral Atlas (the latter being published by the E.U. Press in 1963). For the International Council of Scientific Unions he served on the Special Committee for the IQSY (1962-67), attending the meeting of this Committee in Florence, and the ICSU Assemblies in Rome, Madrid and London.
As an academic meteorologist he was a member of the British Meteorological Research Committee (1955-70), and acted as Chairman of its Instruments and Physical Sub-Committee (1961-64), and of its Synoptic, Dynamical and Climatological Sub-Committee (1964-66). During his Chairmanship of these Sub-Committees much appreciation was expressed of his wide knowledge and sound judgement in the research field. His own publications run to more than seventy papers-almost all in single authorship. He had intended after his retiral to complete a book-already well advanced-on atmospheric optics, and to complete an analysis of the auroral data collected over a complete sunspot cycle of twenty-two years from 1954 to 1975. His death was untimely if only because there was still much that he hoped to do.
Mr Paton was a courteous and kind man whose quiet manner and clear mind made him an ideal member of a committee and a gracious ambassador for British science. He had the unique gift of forming bonds of friendship with everyone he met and worked with. The supreme example of this was his close friendship with C T R Wilson, whose elder daughter has written:
When our father retired to Edinburgh in 1936, he and James Paton at once became friends. They had many interests in common besides meteorology, and they shared a great love for the hills. At an early stage in their acquaintance they went for a Pentland walk together. After the war they climbed some of the Arran peaks. The friendship deepened as the years went on and we feel we owe James a great debt of gratitude for the happiness this friendship brought to our father in his old age.Indeed, old age was quite forgotten when he was in the company of James and his friends at the weekly 'Alcovian' lunches or on flights over the Western Isles.
Many of his friends would have rejoiced if James Paton's contribution to international science could have been acclaimed by his appointment to a university professorship.
Mr Paton's life of dedication to his work was made possible by his wife's constant support, by her meticulous attention to his diet, and often by her help with recordkeeping during the night watches. The last five years were saddened by her long illness, and she survived her husband for only four months. To the members of their family, a son and two daughters, our deepest sympathy is expressed.
His Fellowship of the Society dated from 1946.