Lewis Fry Richardson “The Father of Weather Forecasting”
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D f C f o s n o c i Lewis Fry Richardson “The father of Weather forecasting” t seems almost a dissertation in a competition for the time-step were 3 hours, inconceivable that Lewis a Fellowship at King’s College, then 32 individuals could just Fry Richardson (1881 – but apparently mathematicians compute two points so as to 1953) could have computed from Trinity College were of the keep pace with the weather, if I opinion that this was we allow nothing for the very the first numerical solution of the partial differential “approximate mathematics and great gain in speed which is equations governing the were not impressed” 3. Richardson invariably noticed when a weather 1, by hand, and whilst never returned to Cambridge. complicated operation is serving as an ambulance divided up into simpler parts, driver at the French front in Instead, in 1913, he joined the upon which individuals the 1914-1918 war. Yet that is Meteorological Office, as specialize. the truth of the matter, for he Superintendent of the was an extraordinary man. Eskdalemuir Observatory, If the co-ordinate chequer Scotland. It was here that he were 200 km square in plan, Born in Newcastle upon Tyne in worked on numerical methods for there would be 3200 columns the north-east of England, he was forecasting the weather, writing a on the complete map of the the youngest of seven children first draft of the book 1 which was globe. In the tropics the from Quaker parents. Following eventually to be published in weather is often foreknown, early education at Bootham’s 1922. He resigned in May 1916 so that we may say 2000 active Quaker school, York, and two and joined the Friends Ambulance columns. So that 32 x 2000 = years at Durham College of Unit in France, working alongside 64,000 computers would be Science (eventually becoming the French military ambulances, needed to race the weather University of Newcastle upon transporting wounded soldiers, for the whole globe. That is a Tyne), he studied physics at often under shell fire. Over the staggering figure. King’s College, Cambridge, next two years he refined his graduating with a first, in 1903. numerical methods and carried Perhaps in some years' time it He remained at Cambridge for out the forecast described in his may be possible to report a ten years, holding a number of 1922 book, essentially providing simplification of the process. research posts and positions in the first ‘CFD’ solution of the But in any case, the industry. It was while working as Navier-Stokes equations which organization indicated is a a chemist with the National Peat govern fluid flow. Let us read central forecast-factory for the Industry Limited, 1906 -1907, what Richardson has to say about whole globe, or for portions that he was faced with the task his computations and in particular extending to boundaries of calculating the percolation of his imaginings of a “forecast- where the weather is steady, water through peat. This is a factory”: with individual computers diffusion problem and so is specializing on the separate governed by the Laplace The Speed and Organization equations. Let us hope for equation, but the difficulty he of Computing 1 their sakes that they are found was that the boundary of “It took me the best part of six moved on from time to time the region had a complex weeks to draw up the to new operations. topography, meaning that exact computing forms and to work solutions could not be found. In out the new distribution in After so much hard reasoning, anticipation of his later work in two vertical columns for the may one play with a fantasy ? the numerical modelling of first time. My office was a Imagine a large hall like a weather, he based his solution on heap of hay in a cold rest theatre, except that the circles a finite difference methodology. billet. With practice the work and galleries go right round Following publication of his of an average computer might through the space usually methodology 2 he submitted it as go perhaps ten times faster. If occupied by the stage. The 36 bench mark january 12 D f C f o walls of this chamber are painted to maintain a uniform speed of of the computing theatre. s n to form a map of the globe. The progress in all parts of the globe. o c ceiling represents the north polar In this respect he is like the In a basement an enthusiast is i regions, England is in the gallery, conductor of an orchestra in observing eddies in the liquid the tropics in the upper circle, which the instruments are slide- lining of a huge spinning bowl, Australia on the dress circle and rules and calculating machines. but so far the arithmetic proves the antarctic in the pit. But instead of waving a baton he the better way. In another turns a beam of rosy light upon building are all the usual A myriad computers are at work any region that is running ahead financial, correspondence and upon the weather of the part of of the rest, and a beam of blue administrative offices. Outside the map where each sits, but light upon those who are are playing fields, houses, each computer attends only to behindhand. mountains and lakes, for it was one equation or part of an thought that those who compute equation. The work of each Four senior clerks in the central the weather should breathe of it region is coordinated by an pulpit are collecting the future freely.” official of higher rank. Numerous weather as fast as it is being little "night signs" display the computed, and despatching it by This is a remarkable vision, in which instantaneous values so that pneumatic carrier to a quiet ‘computer’ means only one thing: a neighbouring computers can room. There it will be coded and human calculator. read them. Each number is thus telephoned to the radio displayed in three adjacent zones transmitting station. During his time in France, so as to maintain communication Richardson had calculated the to the North and South on the Messengers carry piles of used weather for a six hour period over map. From the floor of the pit a computing forms down to a Germany, applying a precise and tall pillar rises to half the height storehouse in the cellar. detailed implementation of an of the hall. It carries a large In a neighbouring building there algorithm outlined by the pulpit on its top. In this sits the is a research department, where Norwegian scientist Vilhelm man in charge of the whole they invent improvements. But Bjerknes. It was a spectacular theatre; he is surrounded by there is much experimenting on failure, greatly over-predicting the several assistants and a small scale before any change rate of pressure rise. The messengers. One of his duties is is made in the complex routine mathematical techniques were bench mark january 12 37 D f C f o s n correct, but we now know that The Richardson number is a found on page 66 of his 1922 o the initial conditions which crucial parameter in the field of book, which incidentally is still in c i Richardson used were ‘noisy’ and atmospheric dispersion. For his print - as a 2007 second edition needed to be ‘smoothed’. In contributions to the field of with foreword by Peter Lynch. addition, Richardson’s meteorology, he was elected as a computational time-step was too Fellow of the Royal Society of “Big whirls have little whirls large. Peter Lynch 4 provides an London, in 1926. that feed on their velocity, and interesting analysis of little whirls have lesser whirls Richardson’s prediction. It was in 1926 that Richardson and so on to viscosity” completely changed his field of Nevertheless, through his research, to psychology, again Lewis Fry Richardson is most audacious calculations Richardson making important contributions – certainly an ‘Icon of CFD’, from had shown that numerical in particular in experimental and the days of ‘human computers’. techniques could be applied to mathematical modelling methods solve what appeared to be in the field of sensory perception. intractable physical problems. In 1929 he moved to the Technical College in Paisley, but AUTHOR INFORMATION Richardson rejoined the Met. from 1935 his research shifted to Chris Lea I Lea CFD Associates Office upon his return from yet another field; mathematical [email protected] France in 1919. However, when theories of human conflict and the Met. Office was brought into the causes of war. He pursued the Air Ministry at the insistence these studies until his retirement, of Winston Churchill – and the in 1943, and in the process was Air Ministry controlled the RAF - first to characterise the irregularity Richardson’s pacifist convictions of borders between countries by meant that he had no option but an index which we now recognise to resign. He continued his to be a fractal dimension. research whilst lecturing at However, his research efforts did Westminster Training College, not end upon retirement, as in where he taught physics and 1948 he published a key paper 5 mathematics to prospective on the diffusion of particles in school teachers, publishing turbulent flow, apparently based numerous papers and making on experiments in which he and outstanding contributions in the Henry Stommel threw parsnips meteorological field. He gives his into Loch Long – close to his last name to the Richardson number; home. a key non-dimensional parameter Richardson was a bold visionary for turbulent flows affected by whose work has had a lasting stratification caused by buoyancy.