Downloaded 10/09/21 07:23 PM UTC Sydney Chapman 1 Harry Wexier, 1911-1962, First Wexier Memorial Lecturer Excellent and Devoted Student Ol Our Wonderful
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Mthe r Memorial lecture At its meeting in October 1963, the Council of the American tinguished Public Service Award, the National Civil Service Meteorological Society approved establishment of an annual League Career Service Award, and (posthumously) the Carl- lectureship in honor of the late Dr. Harry Wexler. At a sub- Gustaf Rossby Award of the American Meteorological Society sequent meeting, January 1964, the Council voted that the "for his contributions to knowledge of the atmosphere heat Wexler Lecture be given at the Annual Meeting of the So- balance and dynamic anticyclogenesis, for his interdisciplinary ciety, preferably in the evening of the first day of scientific studies in meteorology, oceanography, and glaciology, and for sessions. Dr. Sydney Chapman was invited to present the his outstanding leadership in international programs in the first Wexler Lecture on Monday evening, January 25, 1965. atmospheric sciences." Dr. Wexler, Director of Meteorological Research for the Dr. Sydney Chapman, internationally esteemed geophysicist, United States Weather Bureau for fifteen years, was taken is a fitting choice to be the first Wexler Lecturer. Staff mem- from the research scene at the time when so much of the ber of the High Altitude Observatory, Boulder, Colorado, research that he had inspired and participated in was just beginning to come to fruition. He was one of the first to advisory scientific director of the Geophysical Institute, Uni- consider and advocate the use of artificial satellites for me- versity of Alaska, and senior research scientist at the Institute teorological purposes as well as one of the first scientists of of Science and Technology, University of Michigan, Dr. Chap- stature to express concern about the effect of rocket and man has made investigations of the atmospheric tides, of the nuclear explosions on the atmosphere. He served on many composition of the atmosphere, of the emission of nocturnal national and international committees. His interest in the light and of the ionization of the higher atmosphere, all atmosphere extended from pole to pole—he was Chief Sci- testifying to the extent and breadth of his interest in the entist for the U. S. Antarctic Program of the International atmosphere. Geophysical Year—and from climatology to hurricanes—he As president of the Special Committee of the International participated in the first aircraft penetration of an Atlantic Geophysical Year, he has exemplified the spirit of interna- hurricane. His many awards in recognition of his notable tional scientific cooperation. He is an Honorary Member of contributions to the atmospheric sciences included the Losey the American Meteorological Society, as well as of the so- Award of the Institute of the Aerospace Sciences, the U. S. cieties and academies of many other nations. Most recently Air Force Award for Exceptional Service, the Department of he has been presented with the Copley Medal, the highest Commerce Exceptional Service Medal, the U. S. Navy Dis- award of The Royal Society, London. 226 Vol. 46, No. 5, May 1965 Unauthenticated | Downloaded 10/09/21 07:23 PM UTC Sydney Chapman 1 Harry Wexier, 1911-1962, First Wexier Memorial Lecturer excellent and devoted student ol our wonderful His background To all those of us who had enjoyed the privilege of personal friendship with Harry and contributions Wexier, the news that this Society had created a Memorial Lectureship in his honor was both agreeable and in no way surprising. His untimely death, which we can never cease to regret, took some decades from the expected duration of his career. But despite this, he achieved high distinction in our great branch of natural science, and played a mem- orable part in American and World meteorology. There may, indeed, be some encour- agement for younger scientists in the example he gave of how much can be achieved, how permanent a mark may be made, in a career so relatively brief. No one, I feel sure, will dispute the fitness of the designation of Harry Wexier, in the title of this first memorial lecture of the series, as an excellent and devoted student of our wonderful atmosphere. Let me recall some phrases from a tribute by R. C. Sutcliffe, F.R.S. (1962), his opposite number in British meteorology, who is certainly more capable than I am of fully understanding and appreciating Harry Wexler's work. He wrote of Harry Wexier as a major figure in the meteorological world, an original scientist of high rank, with a strong urge towards mathematical physics and theoretical understanding, who amidst his wide interests was recognizably a weatherman and climatologist. Par- ticularly cited were his work on anticyclones (Wexier, 1937, 1943, 1951a), his discussion i Dr. Chapman's current affiliations are: High Altitude Observatory, Boulder, Colo.; Institute of Science and Technology, The University of Michigan, Ann Arbor, Mich.; and Geophysical In- stitute, University of Alaska, College, Alaska. Susan Wexier, daughter of the late Dr. Harry Wex- ier, and Dr. Raymond Wex- ier, his brother, examine the meeting program with Dr. Sydney Chapman (cen- ter), just before the First Wexier Memorial Lecture. Bulletin American Meteorological Society 227 Unauthenticated | Downloaded 10/09/21 07:23 PM UTC Vol. 46, No. 5, May 1965 of the normal atmospheric regions of heating and cooling (Wexier, 1944), and his paper "The Antarctic convergence—or divergence" (Wexier, 1959). Harry Wexier was trained at Harvard in mathematics, the subject of his first degree. It was a good basis for his M.I.T. graduate work in meteorology. For a brief period, students of meteorology at the University of Chicago were fortunate in experiencing his influence as their professor. Apart from that, during the 27 years of his working career he was in government service, in a variety of capacities. They included service with the Army Air Force as instructor and research executive. In some circles government serv- ice is thought to be deadening; but Harry Wexier was far too alive and enthusiastic, too original and vitally human, to be deadened. Instead he enlivened his surroundings and fellow workers. For the last fifteen years of his life he directed the research program of the U. S. Weather Bureau, in which he had held his first professional post as a young man. From 1946 onwards he initiated and guided many of the Weather Bureau's most important research projects. Their results are recorded in the impressive series of papers that have issued from the Weather Bureau during the last two decades, by his colleagues and himself. One manifestation of his friendly and cooperative nature, as well as of the team nature of much modern research, is the number of his joint papers. They are about 30 per cent of his total production, of nearly a hundred papers. His work in During the coming years one may expect that successive Harry Wexier Memorial Lec- the upper turers will review particular parts of his work, which gives ample scope for such treat- atmosphere ment. Obviously no one lecture could cover his achievements even in bare outline. On this occasion I shall refer specially, though briefly, to his work and interest in the upper atmosphere. It is natural, indeed necessary, that many meteorologists should confine their studies almost exclusively to the tropospheric weather region of the atmosphere. That region was also the main concern of Harry Wexier. But his interests extended to all levels of our atmosphere, and also to the atmospheres of other planets. I will limit myself to a few examples. He recognized that ozone, generated and mainly located in the stratosphere, is a valuable trace substance whose variations at and above ground level could throw light (Wexier, Moreland and Weyant, 1960) on Antarctic me- teorology, and on interchanges between stratosphere and troposphere, across the gap in the tropopause that is associated with the mid-latitude jet stream (see Fig. 1); he discussed also (Wexier, 1950a, 1951b) the possible effects of ozonospheric heating on sea-level pressure. FIG. 1. Schematic rep- resentation of winter ozone cycle in Antarctica. (From Wexier, Moreland and Weyant, 1960, courtesy of Monthly Weather Review) 228 Unauthenticated | Downloaded 10/09/21 07:23 PM UTC Bulletin American Meteorological Society The second example is his interest in dust. It was the subject of one of his earliest papers (1936), and of three later ones (Wexler, 1951c, d, 1952). The last of these is an excellent account of volcanoes and their possible influence on world climate, for general scientific readers; it gives a sympathetic but critical account of the theory proposed by his eminent Weather Bureau predecessor Humphreys, that volcanic dust may be an im- portant factor in long-range climatic variations. The third example is provided by his discussions of the vertical propagation of storms —either downward from the outer fringes of the atmosphere, where solar radiation first encounters appreciable absorption, or upward from the earth's surface, where about half of the incoming radiation is finally absorbed, and transformed into potential, kinetic, and internal energy of the air (1958; see also 1953). My fourth and last example is his discussion of annual and diurnal temperature varia- tions in the upper atmosphere (Wexler, 1950b). He concluded that in the upper ozono- sphere in the higher latitudes the annual variations might be as great as 75C, and that the average diurnal range there might rise to from 10 to 15C. These conclusions are now being borne out by the extensive rocket measurements made in recent years (Webb, 1965). Harry Wexler's wide knowledge of the upper atmosphere was indicated by the 1957 Report of the American Geophysical Union Committee on this subject; he was the Chair- man, the members being Johnson, Kaplan, Kellogg, Newell and Whipple, with Fritz as consultant.