[Graham] Sutton was privileged in his final year at school to receive almost individual coaching in mathematics and chemistry for the Higher Certificate of the Central Welsh Board and was able to proceed with the help of County and University Scholarships to the University College of Wales, Aberystwyth, in 1920. There he graduated in 1923 with first class honours in pure mathematics and subsidiary applied mathematics, physics and chemistry.

He had a short initial posting to Shoeburyness for work on meteorological corrections to gunnery procedures but in the following year was seconded to the Chemical Defence Experimental Station, Porton, where he embarked upon his major scientific research on atmospheric turbulence and diffusion. ... By the time Sutton joined the group there had been useful progress in observing and understanding the complex properties of atmospheric flow relevant to the dispersion of gaseous and particulate material injected locally into the atmosphere.

The theory of eddy diffusion in the atmosphere put forward almost simultaneously by G I Taylor and L F Richardson in England and by W Schmidt in Austria is a direct generalisation of the classical theory of molecular diffusion. It is assumed that the mass effect of the eddies is entirely similar, except for a scale difference, to that of the molecules ; thus we find an eddy-diffusivity of the order of $10^{2}$ to $10^{11}$ cm$^{2}$/sec replacing a molecular diffusivity of the order of $10^{-1}$ cm$^{2}$/sec in entirely similar differential equations. Recent researches [in the Davies-Sutton 1931 paper], however, have shown that the difference between the eddy structure of a turbulent fluid and the molecular structure of a fluid at rest is more than one of scale, and it is now clear that there is need of an extended theory to express this difference. The failure of the earlier theory to account for the phenomenon of atmospheric diffusion has been made evident by the enormous variations found in K, the eddy conductivity. Richardson has evaluated K for the diffusion of smoke over short distances, for the distribution of volcanic ash, and for the scatter of small balloons, and has found K's varying from $10^{4}$ to $10^{8}$ cm$^{2}$/sec. Other writers have given estimates varying from $10^{2}$ to $10^{11}$ cm$^{2}$/sec, and in general it has been found that K increases rapidly with the scale of the phenomenon. The present paper is concerned with an attempt to define a new diffusion coefficient which is constant over a field of a few hundred metres to hundreds of kilometres. The basic idea, that the rate of diffusion is governed by what is termed the "effective eddy" is not entirely new; it is inherent in much of Richardson's work. In the earlier theory it was assumed that the size of the effective eddy remained constant; here it is assumed that it varies with the distance travelled by the diffusing cluster.

The author wishes to acknowledge with gratitude the invaluable assistance given to him in the course of these researches by Mr D Brunt, M.A., and Mr E LI Davies, M.Sc., both of the Meteorological Office.

Sutton's wise and constructive influence on the Porton wartime programme was obvious to all concerned. Apart from the need for a thorough appreciation of the technical requirements, there was the equally demanding task of ensuring the harmonious and effective deployment of many scientists with different disciplines, working in groups and as individuals, some imported specially for the war effort from university and industry, many of them now operating in close conjunction with service personnel. W R Lane, a senior contemporary Porton physicist, writes of Sutton's contribution at that time as follows: "Sutton had a deep feeling for the inter-disciplinary approach to problems, and with his mathematical expertise and meteorological background he made a major contribution to the work of the Establishment. He encouraged new ideas and independent thinking and he permitted a freedom of action which was greatly valued by his associates."

He greatly enjoyed this temporary return to academic life where, in addition to his teaching duties, he maintained his research activity. In these years he published the key papers which established his reputation.

The consequences were wide-ranging, for they provided for the first formulae representing the effect of meteorological conditions on the distribution of concentration downwind of a continuous release of gas or particles at ground level. Sutton's point-source formula, at first in restricted use in chemical warfare studies, became widely known in the context of industrial pollution.

In this Monograph I have attempted an account of an aspect of dynamical meteorology which is now recognised as a study of major importance, not only because of its intrinsic interest and the fundamental part which it plays in the science of meteorology as a whole, but also because of its significance in economic, military and industrial spheres. The theory of atmospheric turbulence is more mathematically developed than those parts of dynamical meteorology which treat of large-scale motions of the atmosphere and I have considered the subject throughout as a branch of mathematical physics.

As its title indicates, this is a book about the theoretical aspects of flying. It is not concerned with the problem of aircraft design, which is the province of the engineer, and nowhere does it touch upon the actual technique of flying. In short, it is an attempt to explain to the layman something of a branch of applied mathematics, called aerodynamics, which lies at the root of all matters appertaining to mechanical flight. I have written the book because I believe there are many people who would like to know more of these matters. This means putting into plain English much which is usually expressed in the language and notation of mathematics, an interesting but never very easy task for the author who must, of necessity, be steeped in that notation himself.

In his last years Sutton returned to Wales, to Swansea, and an interesting glimpse of his continued concern with organisation is provided by the fact that the house he built for his retirement at Swansea was of identical design to the one he had earlier built at Bracknell. In this way all the furniture fitted perfectly and the upheaval of moving house was reduced to a minimum.

Sutton quickly found himself involved as a local magistrate and, slightly further afield, as a very welcome member of Council of Aberystwyth University College, of which he later became Vice-President. He gave himself wholeheartedly to the tasks deriving from his membership of Council, most aptly perhaps as Chairman of the Buildings Committee. He and members of his family - brother, sister, wife - had as undergraduates known only the old college buildings on the sea front; he returned in 1963 to open the new Physical Sciences building on the post-war campus up the hill.

[He] was Vice-President of University College Wales, Aberystwyth from 1967 to 1976. He was elected a Fellow of the Royal Society in 1949, appointed CBE in 1950 for distinguished service to government scientific work, and knighted in 1955 for services to mathematics and science. He received many honours including Honorary DSc (Leeds), Honorary LLD (Wales) 1949; and honorary membership of several scientific and American societies, and he was presented with: the President's Gold Medal of the Society of Engineers (1957); Symons Gold Medal, Royal Meteorological Society (1959); International Meteorological Organization Prize (1968); and Frank A Chambers Award, Air Pollution Control Association (1968).