Volume 58(1) - January 2009

Fifty years ago

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WMO Bulletin Vol. VIII, No. 1
January 1959

The picture on the cover

A message to meteorologists

At the close of the International Geophysical Year (IGY), we would like to express, on behalf of the World Meteorological Organization, thanks and appreciation to all meteorological services of the world for their whole-hearted collaboration in this vast project, which provides yet another demonstration of the international spirit for which meteorologists have long been renowned. A special tribute must be paid to the thousands of meteorological observers throughout the world upon whom the IGY imposed many additional duties. We are confident that the same enthusiastic support will continue until the last of the forms containing the meteorological observations has been received at the WMO Secretariat, thus completing the collection of data which constitutes a unique contribution to future developments in the science of meteorology.

Signed:
A. Viaut, President
D.A. Davies, Secretary-General

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Contents

The January 1959 Bulletin carried articles entitled “WMO and the development of meteorology”, “Meteorological problems in atomic energy”, “An instrument for counting local lightning flashes” (submitted by the International Radio Consultative Committee), “World meteorology: retrospect and prospect” and “New British ocean weather ship”. It also covered the second session of the Commission for Agricultural Meteorology, collaboration with other international organizations, International Geophysical Year, activities of regional associations and technical commissions and technical assistance.

WMO and the development of meteorology

Achievements and future prospects

During the last eight years, there have been two sessions of Congress, 11 sessions of the Executive Committee, 15 sessions of technical commissions and a large number of meetings of working groups. At the same time, the participation of WMO representatives at sessions of other organizations has been constantly increasing in the face of the growing demand for such representation.

The immense tasks thus placed before the Organization have been successfully carried out, in spite of relatively modest budgets, thanks to the generous invitations from our Members, the ability and unselfishness of our experts and to hard work. Most of the latter was the result of unflagging devotion to duty on the part of the Secretariat staff under the leadership of the late G. Swoboda—who was responsible for ensuring that the vital transition from the former IMO was made without a hitch—and subsequently under that of the dynamic D.A. Davies, both of them efficiently seconded by the Deputy Secretary-General, M.R. Rivet.

Achievements of lasting importance

Fortunately, all this effort was not in vain. The many achievements of which WMO has every right to be proud include the following:

  • Establishment of the Technical Regulations which—with the barometer and radiosonde comparisons—contribute to the universal standardization of meteorological procedures and practices;
  • Publication of a large number of Technical Notes and the Cloud Atlas, the success of which has exceeded all our expectations;
  • The continuous improvement of the observing networks and transmission channels, whose efficiency and regularity could serve as an example to other branches of science which are passing from the laboratory stage to the synoptic stage long after meteorology;
  • International cooperation in arid zone problems and the development of water resources
  • The large-scale participation in the International Geophysical Year programme, including the creation of a Meteorological Data Centre in Geneva;
  • Ever-increasing participation in the United Nations Technical Assistance Programme.

All these achievements are in harmony with the aims of our Organization, one of the most important of which is to “further the application of meteorology to aviation, shipping, agriculture and other human activities”. More special attention should perhaps be given in the near future to another or our aims, namely “to encourage research and training in meteorology and to assist in coordinating the international aspects of such research and training”.

New spheres of activity

In the meantime, the Organization has had to tackle some entirely new and urgent problems such as those connected with the use of atomic energy and the introduction of commercial jet aircraft. Thanks to the cooperation of those Members which have willingly lent the services of experts in these fields, the Executive Committee has been able to take appropriate and effective action. …

The collaboration of our Organization has been solicited in another important field, that of hydrology, because it has become apparent that there is need for intergovernmental coordination of hydrological observations and investigations throughout the world. The Economic and Social Council of the United Nations has recommended that the responsibilities of WMO be extended to cover a large part of this field. … a preliminary inquiry carried out by the Secretariat has shown that many Members would be in favour of such a step, which would increase the importance and prestige of the Organization. The final decision lies with Third Congress.

… I think that the results obtained by WMO are such as to convince the governments of its Members that the best possible use has been made of the contributions which they pay. … F.W. Reichelderfer [has] pointed out quite rightly that “they [meteorologists] have of necessity practised their profession with minimum facilities and meagre information and data—facilities that would be regarded as less than reasonable standards in other physical sciences”. This spirit of economy—which is a sort of professional characteristic of meteorologists—has resulted, when transferred to the international level, in WMO being one of the best investments amongst the international organizations.

Problems for future study

We can justifiably be proud of the results already obtained, but we must ensure that this very praiseworthy desire for economy does not lead to harmful cheese-paring. To use an anatomical metaphor, our Organization can be slim but it must not run the risk of becoming rickety.

This is particularly important at the moment, for meteorology is now undergoing an evolution which with the passage of time may one day be considered as a revolution. The traditional charts showing the isobars, fronts and air masses, used exclusively until quite recently, are now supplemented by contour charts which may in turn be partly replaced by tropopause and streamline charts. Our knowledge of the general circulation, jet streams and the structure of the tropopause is constantly growing. Study of the upper winds between 20 and 40 km north of the Tropic of Cancer show, for example, that in addition to the seasonal variations in the easterlies, there are also variations in speed and direction which merit closer study in order to determine their cause and their relationship with the development of the wind field, up to at least the level of the tropopause. Moreover, it is possible to confirm beyond all doubt the existence of a layer with a mean thickness of 7 km, lying 2 km above the tropopause, in which wind speed decreases considerably and the temperature variations are very small: a layer, therefore, where the conditions, free from clouds and probably of turbulence, are ideal for long-distance flights by the turbo-propelled aircraft of tomorrow. Thus, every day brings new confirmation of the notion of the worldwide interdependence of all atmospheric phenomena.

The charts prepared by the meteorological services formerly covered areas of varying, but often limited, extent. Today, the drawing of hemispheric charts will have to become a part of the daily work, at least in a certain number of services; planetary charts will, in their turn, soon be introduced into routine practice.

Parallel with the increase in the intensity of meteorological work, there is also an expansion in its scope. Observations of radiation, ozone, the chemical composition of the air and radioactivity, which hitherto were not very widespread, are acquiring increasing importance; they are no longer made only at isolated stations, but also in organized networks. This development has been speeded up by the International Geophysical Year and it would be regrettable if these new networks were to be closed down.

Application of new techniques

New techniques are on the point of making a valuable contribution to this mass of data. It is still too early to make a complete inventory of all that meteorology may expect to obtain from the extra-atmospheric observations made by means of rockets or artificial satellites. We can already imagine, however, that the measurements of the Earth’s albedo which these observations include, will be of the greatest value to meteorologists. The first photographs taken over vast areas of clouds also open up very encouraging perspectives.

The transmission and application of this immense accumulation of information raises considerable problems, for which solutions can only be found by ever-expanding international coordination which our Organization alone is able to ensure, provided that it has the necessary means. All meteorological services should preferably possess their own transmission networks. They would then be sure of being able to obtain directly and with the least possible delay the basic synoptic data essential for the regular operation of their forecasting services, which have to provide the information needed for a large number of human activities dependent on changes in meteorological conditions.

The progress which is being made in numerical weather forecasting has led to the increasing use by meteorological services of electronic computers. The efficiency of these machines is to a great extent linked with the possibility of satisfying their huge appetite for fresh observations. This new obligation makes it more than ever essential to keep the international meteorological telecommunications plans up to date.

One of the heaviest and most urgent tasks faced by meteorologists is the processing of the International Geophysical Year data. Immense benefits for humanity may be expected from this, the most important scientific enterprise of all time. All meteorologists are certainly prepared to make every possible effort to ensure that these benefits are acquired without too much delay.

There is a proverb—Union is strength. For many years meteorologists throughout the world, intent on problems relating to the atmosphere, which recognizes no political frontiers, have shared the same preoccupations. In this undisputed field of understanding, the human contacts happily made possible by our meetings lead to the development of ever closer links of friendship. It is this fraternal unity, transcending all our changes of fortune, which offers the greatest encouragement in the face of the immense tasks which are already known and those which are still to come.

A. Viaut
President of WMO

Meteorological problems in atomic energy

In September 1958, Geneva became the scene of what is reported to have been the largest international conference ever to be held. For two weeks, more than 5 000 scientists and observers from many parts of the world gathered in the Palais des Nations to take part in the second International Conference of the United Nations on the Peaceful Uses of Atomic Energy. …

The interest and activities of WMO in the meteorological aspects of the peaceful uses of atomic energy have already been recounted in a previous issue of the Bulletin (Vol. VI, No. 2). In particular, reference was made to the work of the WMO Panel of Experts on Atomic Energy. In connection with the conference referred to above, the panel prepared a document on the meteorological aspects of atomic energy which was submitted by WMO to the conference. This document was selected as one of the relatively few documents to be presented verbally to the conference and the present article consists essentially of the statement made by the Secretary-General in presenting the paper.

There are two main reasons why the meteorologist is interested in the peaceful uses of atomic energy. In the first place the release into the atmosphere of radioactive materials (either as effluent or by accident) and their subsequent movement is an aspect of the overall development of the peaceful uses of atomic energy to which much attention has of necessity to be given. The study of the movement in the atmosphere of any such materials is one in which meteorological factors are of direct and predominating concern and this aspect of the peaceful uses of atomic energy is thus closely linked to meteorology.

Secondly, radioactivity and techniques peculiar to the radiochemists and radiophysicists are becoming increasingly important to the science of meteorology and open up new possibilities for meteorological observational methods which previously could not be contemplated.

Safe operation of reactors

With regard to the first aspect, namely the help which meteorology may provide for the safe operation of reactors and other atomic installations, it should be stressed that the movement of radioactive material in the atmosphere and its deposition on the surface is governed largely by meteorological conditions, such as lateral displacement by winds at various levels and vertical displacement by vertical movements in the atmosphere, particularly atmospheric turbulence.

In this connection, reference may be made to the well-known Richardson theory of turbulence and the equally well-known theory of Sutton on the diffusive properties of the atmosphere and their dependence on meteorological parameters.

Another important meteorological aspect of this problem is the stratospheric/tropospheric interchange. The reservoir of radioactive material accumulating in the stratosphere and slowly being transferred downwards to the troposphere establishes the need for further meteorological studies and this problem is specifically referred to in the recent report of the United Nations Scientific Committee on the effects of Atomic Radiation.

It should perhaps also be stressed that the meteorological factors affecting the siting and operation of reactors and other atomic installations have an obvious international aspect. Atmospheric movements pay no respect to man-made boundaries and this is one but by no means the only reason for the interest of WMO in this field. One has only to mention the Windscale* event to demonstrate the international aspects of this problem.

It may be added further that, however, new may be the need for international cooperation in dealing with the various aspects of the peaceful uses of atomic energy, the meteorological aspects of this subject differ little in principle from normal meteorological activities, in which the need for international cooperation has been recognized for about a century and which have been the raison d’être of WMO and its predecessor, the IMO, for about 80 years.

The second important subject, namely the way in which radioactivity and the techniques of the radiochemist or radiophysicist may be useful to the meteorologist, are dealt with below in rather more detail.

Two broad categories may be enumerated: first, the use of radioisotopes as tracers of air movements and second, instruments using the attenuation or scattering of nuclear emissions to obtain density or depth measurement of soil or water.

Use of radioactive tracers

The naturally produced radon or thoron or their daughter-products can be and in some cases have been used to study the vertical mixing of the atmosphere on a scale ranging from centimetres to many kilometres about the Earth’s surface. Then again, the difference in emission of these radioisotopes over land and water permits an easy distinction, in many cases, of the source of an air mass by measuring the natural radioactivity of the air. Other similar examples could be given. Thus, while much has been done, the meteorologist stands to gain still further from experiments designed by himself, particularly if the use of an extensive network of stations measuring atmospheric radioactivity similar to the long-established worldwide meteorological network is possible.

Natural radionuclides produced by cosmic rays have been detected chiefly since the development of low-level counters and the discovery of cosmic rays themselves. More than a half dozen have been reported, many with half-lives of tens of days to a few years—a timescale of many weather phenomena. Among other uses they can be studied in order to trace the exchange of air between the stratosphere and troposphere. Peters and his colleagues in India have demonstrated how one may use the ratio of certain of these isotopes to find the amount of recent stratospheric air which is in the troposphere. … in the latitudes of India, there was essentially no recent stratospheric air in the lower levels, a comforting verification of meteorological prediction.

Man-made radioisotopes have already been useful in tracing air masses. … information from low-level radioactivity can be used for meteorology. This information on atmospheric dilution can in turn be applied to reactor emission problems.

Radioisotopes created during nuclear tests, while not intended for geophysical purposes, have nevertheless been valuable in studying large-scale phenomena. Meteorologically deduced trajectories have been verified to distances of several thousand kilometres by following fission products from test. Although constant-level balloons present an excellent means of following air parcels, certain difficulties arise in their use at lower levels and the radioactive debris has been almost the only tracer available at these lower levels. The rate of lateral spreading of nuclear clouds obtained from the spread of debris also offers essentially unique data on atmospheric mixing for movements of several thousand kilometres and between hemispheres.

It has been found that fission-product debris has a mean life of about 20-30 days before being rained out of the atmosphere. The radon results suggest a mean removal time of only about 10 days. It is probable that the difference is due to injection altitude, the radon being introduced at the ground or within the rain-bearing layer and the debris generally above this level—or above about 5 km. The tritium introduced by the 1954 Pacific tests also showed about a 30-40 day mean residence time. This tritium, too, was probably introduced mainly above the rain-bearing level and took time to mix downwards.

A study of strontium-90 fallout has led … to the conclusion that air leaves the stratosphere preferentially in the temperate and-or polar latitudes of the Earth. This inference from the strontium-90 fallout as well as a seasonal variation, with more spring than autumn fallout, tends to confirm a model of tropospheric/stratospheric exchange suggested in England ... from other information.

The attenuation of gamma rays has been used to measure the water content of snow pack. By making the equipment automatic and by telemetering the results to a home base, such equipment can now provide information from otherwise inaccessible areas during winter. The height of a water level in a river or lake can likewise be measured by attenuation. Many countries also have devices to observe soil moisture by the scattering of fast neutrons and the density of soil, essentially simultaneously, by the scattering of gamma rays.

The radioisotope carbon 14 with its 5 700 year half-life has also been used in a number of meteorological investigations. In some air pollution studies, the proportion of recent to fossil carbon has been determined in an attempt to trace the source of damage-producing contaminants. Another use is the measurement of the ratio between carbon-14 and carbon-12 as an indication of the growth of the atmospheric content of carbon dioxide between air and ocean. Mention should also be made of the promising possibilities of evaluating the exchange between the stratosphere and the troposphere by the measurement of the amount of carbon-14 in the troposphere.

In conclusion it may be said that the atomic age opens doors to greater hazards but at the same time to greater opportunities; the science of meteorology will play an important role in minimizing these hazards and in exploiting these opportunities.

D.A.D.

International Geophysical Year

By the time this article appears, the International Geophysical year will have closed, at least as regards the observational programme. The important task of collecting and publishing the IGY meteorological observations will, however, not be completed for at least two years and the research work based on these observations will continue for many years. It is therefore too early to attempt to assess the ultimate scientific value of the IGY. At this stage the most that can be said is that, thanks to the IGY, meteorological research workers will soon have at their disposal for the first time in history, an 18-month series of checked meteorological observations from over 100 different countries published in a uniform manner.

The fact that almost without exception the meteorological services of the 97 Members of WMO participated in the IGY, along with several meteorological services of non-Member countries, and that they are sending their data to the IGY Meteorological Data Centre in the WMO Secretariat, is a fine illustration of the advanced state of development of meteorology at the national and international level as compared with the other geophysical sciences, in which the number of participating countries is much smaller. This excellent cooperation in the observational part of the IGY meteorological programme is a challenge to the research worker to justify the enormous expenditure of effort which has been made to provide him with the material needed for his researches. At the same time it gives ground for hoping that a similar international cooperation will be achieved, in research projects based on the IGY data.

IGY world synoptic maps

… a resolution was adopted at the fifth session of the Special Committee for the IGY calling on WMO to study the most efficient and expeditious way of having prepared and published a specified series of world synoptic maps and aerological cross-sections based on the IGY observations. Following a request from the chairman of the WMO Working Group on the IGY, this list of maps and cross-sections has now been sent to all Members of WMO. Members have been invited to state to what extent they would be prepared to assist in this project. It will be recalled that the Federal Republic of Germany, the Union of South Africa and the USA are already going ahead with the preparation of a daily series of IGY world synoptic maps for mean sea level and 500 mb. This will represent a substantial contribution to the project now under discussion.

International Geophysical Cooperation 1959

The General Assembly of the International Council of Scientific Unions (ICSU), held at Washington in October 1958, decided to accept the CSAGI proposals for the International Geophysical Cooperation 1959. The text of the ICSU resolution is that “the observational and data collecting activities in the geophysical and related sciences be conducted during 1959 on the same general plan as in 1957-1958 under the direction of the CSAGI, respectively the SCG (Committee for Inter-Union Cooperation in Geophysics) as far as feasible and at such level and in such fields as may be determined by each Participating National Committee”.

In parallel with this action by ICSU, the WMO Executive Committee adopted by postal ballot a resolution agreeing in principle that WMO should collaborate in the IGC. On the basis of this and of a recommendation of the WMO Working Group on the IGY, the President of WMO subsequently approved, on behalf of the Executive Committee, a second resolution in which it is recommended that members and the meteorological services of non-Members should continue so far as possible the IGY meteorological programme throughout 1959. Where it is not possible to continue the full programme, priority should be given to aerological, ozone and radiation observations. A special effort should be made to carry out two high-level radiosonde ascents during the World Meteorological Intervals … As the authorized programme of the IGY Meteorological Data Centre is limited to the collection and publication of IGY data, it has been decided that forms containing the IGC data should not be sent to this Centre at present. The possible extension of the Centre’s programme will be discussed at Third Congress in April 1959 and the arrangements for collecting and publishing the IGC meteorological data will have to be made in the light of the decisions of Congress.

O.M.A.

World meteorology: retrospect and prospect*

Not only in science, but also in everyday life, the mere act of clearly defining or formulating any problem often contains within itself more than half the solution.

It takes most of us practically a lifetime to realize the potency of this cardinal truth. At the time when I joined the South African Meteorological Service in 1933, had I had a clear conception of what the objectives (and unescapable limitations) of meteorological science were, I might have been spared many fruitless and frustrating excursions into by-ways which led nowhere. Undoubtedly many colleagues in meteorology have had similar experiences.

In looking retrospectively at the past quarter of a century, it may therefore serve some useful purpose if I attempt to formulate as concisely as possible and to the best of my ability the fundamental problem or problems confronting all meteorologists who take their science seriously. In making this attempt I shall have to repeat things which I have previously discussed at various times and places, but this seems unavoidable.

The nature of human knowledge

If all activity of the human mind is broadly designated as knowledge, the latter may advantageously be classified into two categories, cumulative and non-cumulative knowledge. Without entering into any lengthy discussion concerning the somewhat diffuse boundary, the main features of each of the two categories may best be grasped by some play of the imagination.

Suppose it were possible for the authors of the Book of Job, the Iliad, Macbeth and Faust to come back to Earth, accompanied, say, by Leonardo da Vinci and Rembrandt, Bach and Mozart, the creator of the Taj Mahal and Michelangelo, Plato and Kant, would these great men have much to learn from our modern men of letters, painters, musicians, sculptors, architects and philosophers?

Apart from the shock they would presumably experience at what passes for literature, music and art in our highly enlightened age, it would soon become apparent to everybody that the rhetorical question we have posed must inevitably be answered in the negative. In other words, very little essential progress has been made in these fields of knowledge during the past centuries.

On the other hand, if any of the great natural scientists of past ages, Euclid, Archimedes or Galileo, were transported back to Earth they would have infinitely much to learn in their various fields to catch up with modern science. Even the great Newton himself, for all his genius, would have to study intensively before he could take an active part in any discussion concerning thermodynamics or wave mechanics. We are therefore justified in classifying the natural sciences as belonging to the category of cumulative knowledge.

Proceeding a step further we may divide the natural sciences into two classes, the exact or mathematical sciences and the descriptive or biological sciences, although the boundary between them is even more diffuse than between our two categories of human knowledge. In general it may be said, however, that the great progress has been made in those sciences which have not been satisfied to be purely descriptive but have striven to explain the phenomena of nature in terms of the ultimate constituents of matter. Although the theory of the transmission of electricity and its useful application had been worked out in great detail, and with immense mathematical ingenuity long before the electron, as the carrier of electricity, had been identified, yet the greatest triumphs of physics in electronics, the development of atomic power, etc., would have been impossible if physicists had not persisted in probing deeper into the actual make-up of the atom and the molecule.

Perhaps apologies are due for this slight excursion into the philosophic field, but none are offered, because I consider this matter as of basic importance as regards our attitude towards the future development of meteorology. The question is whether meteorologists are passively going to permit their science to be relegated to the category of what we have designated as the merely descriptive or biological sciences, and allowed to stagnate, as has largely been the case during the past quarter century, or whether they are boldly going to claim that it rightly belongs to the mathematical sciences, and to accept all this implies.

Having made a decision in our own mind that meteorology has the potentiality of being developed as an exact science, we have at least made one step towards defining the problem facing us. Of course, in considering the task of meteorology, that of describing the motion and physical characteristics of the atmosphere, its temperature, humidity and the visible manifestations of the latter such as cloud and precipitation, it must be evident that, owing to the vastness of the atmosphere, its properties can only be discussed on a statistical basis. Only in exceptional instances can the large-scale motion of the atmosphere by described in terms of mathematical equations, but even the simplest of these are so complex that general solutions are impossible, and we have to content ourselves with approximate numerical solutions made possible by modern electronic computers.

However, the fact that in most cases we have to be satisfied with the study of statistical entities in meteorology need not discourage us unduly. After all, chemistry has developed into a mighty science in spite of the fact that the chemist is not primarily interested in the behaviour of individual molecules, but in statistical averages.

In attempting to assess the potentialities of meteorology and its development as an exact science, we should have liked to deal with the entire field, including weather forecasting, but lack of space prevents this, and in what follows we shall devote our attention exclusively to climatology and its orderly and rational development.

The objectives of world climatology

Let us formulate our problem concerning the future of climatology thus: if climatology had been a fully developed mathematical science it would not have been necessary to send costly expeditions to the Antarctic to determine the climatic features of that continent, which could have been deduced from first principles. Stated differently, the ultimate aim of climatology must be the explanation of all climatological features of the entire atmosphere in terms of the known distribution of land and sea, and of the fundamental physical processes of the absorption of the Sun’s radiation, the evaporation of water, the transport of heat and moisture, etc. Although this may be a somewhat Utopian ideal, it is nevertheless concrete and possibly not quite as unattainable as one may be tempted to think at the outset.

The procedure to adopt in striving towards this ideal clearly does not lie in the direction of theoretical speculation. Any such attempt is foredoomed to failure, as all meteorologists will readily agree. The more arduous alternative is unavoidable—that of first ascertaining the climatological facts and thereafter deducing the mechanics which are responsible for the observed facts. The primary requirement thus remains the direct measurement of temperature, humidity, pressure, winds, etc. New methods of determining the general atmospheric circulation, for example, by deduction from the transport of radioactive tracers, may be most interesting, but at best must be regarded as a very poor substitute for direct wind measurements. Admittedly, immense regions of the atmosphere still remain unexplored, but owing to the exceptional efforts made during the International Geophysical Year we are in a better position than ever before as regards the requisite basic data.

Method of approach

As illustrative of the proposed method of procedure we may consider only the temperature field or the pressure field of the atmosphere but probably it is simpler to choose the latter since the elimination of the daily and half-daily oscillations is quite simple, so that only the seasonal pressure variation need be taken into account.

The first two parameters describing the pressure at any point are undoubtedly the mean pressure and the standard deviation, the latter being a measure of the intensity of the fluctuations and their relationship with, for example, the passage of cyclones and anticyclones, a measure of their distribution in time is essential, which means that the pressure spectrum has to be determined. This can be done either directly or also indirectly by computing the auto-correlation, which is the Fourier transform of the spectrum.

However, at this point, a rather serious difficulty arises. The spectrum is a continuous curve and it is essential to express it in mathematical terms. In the past, spectral analysis of meteorological entities has been sadly neglected, and as yet there is no generally accepted method for presenting spectra. In this connection, WMO could render a signal service to world meteorology by appointing a panel of experts to decide upon the best mathematical expressions for all kinds of meteorological spectral curves. The universal adoption of the recommendations would also eliminate the publication of lengthy frequency tables, which can advantageously be replaced by the numerical values of the parameters contained in the adopted mathematical expressions. For the time being, let us suppose that the spectral curve contains three parameters and accordingly that the pressure characteristics at any point can be adequately expressed in terms of five parameters: mean pressure, standard deviation and the three spectral parameters.

It should be noted that each of these parameters varies in space and with the season of the year and is accordingly a function of the three space coordinates and of time. …

In practically all cases this function is extremely complicated but fortunately, as regards the seasonal variation, it is in general necessary to take into account only the two principal harmonics, the annual and semi-annual oscillations. This implies that for each of our five parameters two amplitudes and two phases have to be determined together with the mean annual value. … let us for a moment consider the way climatological problems are ordinarily dealt with.

In current works on climatology, attempts are sometimes made at offering an explanation of certain irregularities, exhibited, say, by an isobaric or isothermal chart. Thus, in the newly explored region near Antarctica, we may find that the isotherm at some spot A shows a somewhat puzzling southward bulge and in attempting an explanation we discover an area of high pressure to the east of A. The conclusion is that the area around A must experience the advection of warmer air from the north and our temperature anomaly is explained! On a subsequent occasion we relate any abnormality in the pressure field to a corresponding anomaly shown by the isothermal chart, and thus the merry-go-round proceeds apparently to everybody’s delight and satisfaction. Let him who is inclined to take exception to these rather flippant remarks, take the trouble to read in somewhat critical mood certain long-winded modern works on synoptic climatology and convince himself that climatology does indeed need a fundamentally new approach.

The idealized maritime world climate

In attempting further simplification, there is one outstanding fact which we cannot afford to neglect. This lies in the circumstance that on a globe covered entirely by water every climatological parameter must of necessity be independent of the longitude … in other words, longitudinal irregularities must be ascribed exclusively to the irregular distribution of land and sea … However, from the point of view of mathematical analysis the shapes of the Americas, Africa and Eurasia are very intractable and we are apparently confronted by insuperable difficulties, but here again statistical methods may be called to aid. … it is possible to ascribe to every point on the global a measure of its continentality. …

… In a purely maritime climate the value of the pressure, temperature, etc., at two points north and south of the Equator and equally distant from it must of necessity be almost identical, with a phase difference of six months. The slight difference is due to the ellipticity of the Earth’s orbit around the Sun. …

Up to this point we have considered atmospheric pressure only, but with suitable adaptation essentially the same method of analysis can be applied not only to temperature and humidity, but also to winds, precipitation, etc. In all cases, it simplifies matters considerably if the daily variation of any parameter be initially eliminated by considering only its mean value for 24 hours. …

… we have arrived at the point where our real research begins. … a general pattern is sure to emerge and eventually it should be possible to deduce the physical basis of the relationship between the pressure field and the geographical features of the Earth ... A vast field of research is thus opened with the prospect of definite results.

Furthermore we have deduced the climate of a water-covered globe, the advantage gained being the vast simplification due to the fact that every climatological element is now entirely independent of the longitude. Hence the prospect of interpreting the pressure and wind fields in terms of the fundamental hydrodynamical equations, expressed in spherical coordinates and suitably adapted to the statistical case, is very promising indeed. Our initial objective of explaining the principal climatological feature of the atmosphere in terms of fundamental physical processes therefore does not seem to be entirely unattainable. Any comprehensive description of the methods to be employed cannot be given here, first due to lack of space and secondly because they must of necessity depend on the results in the course of the initial detailed analysis described above. In any case it must be evident that a vast field of fruitful research will be opened by the systematic analysis of the different climatological factors in the way indicated. The proposed programme is very comprehensive and can be carried out effectively only by a well-planned cooperative effort of a large number of meteorological services. The rational development of world climatology should accordingly be a matter of full international cooperation as was the assembly of the basic data during IGY.

The task awaiting WMO

From what has been said, the task confronting WMO becomes more or less self-evident.

It is an indisputable fact that relatively little use has been made of the vast amount of meteorological information collected during the 1932-1933 Polar Year. Now, it needs no prophet to predict that much the same is going to happen in connection with the data collected during IGY, unless it is recognized that their digestion and methodical analysis is as great (if not as expensive) an undertaking as was their collection. An astounding measure of international cooperation has been attained in the assembly of the data from all over the globe. Similar international cooperation is essential for the comprehensive analysis of the data if the greatest possible benefit is to be derived from it. And yet it is surprising how little constructive thought has been devoted to the really effective utilization of the information gathered at stupendous cost.

At the second Brussels meeting of the Special Committee for the IGY I proposed the publication of daily world weather charts for the duration of the IGY. This proposal was eagerly and unanimously adopted. At present, the USA, Federal Republic of Germany and the Union of South Africa are busy carrying out the important work entrusted to them. At the same time I also proposed the publication by the three countries of grid-point pressure data at the surface and 500 mb levels. This was done specifically with the object of computing from the published data the five pressure parameters previously discussed. My second proposal had a rather luke-warm reception—to my surprise and dismay. Surely at this stage, it should not be necessary to convince meteorologists that the prospect of fundamental progress is negligible as long as climatology remains purely descriptive! The collected world weather charts, although they have the merit of containing in concise form a record of world weather from July 1957 to December 1958 will remain little more than a set of pretty picture books, unless the numerical data extracted from them be rationally analysed. The availability of world weather data in tabular form is of much greater immediate scientific value than the charts from which they are extracted and failure to recognize this can only be deplored but need not make us unduly pessimistic, since most meteorologists will agree that the time has arrived for a bold progressive move if meteorology is at last to emerge from the doldrums.

The proposed programme of climatological research, including the comprehensive initial analysis of the principal climatological elements on a global scale, must patently be an international undertaking organized by some central agency, which can be no other than WMO. Different countries will presumably undertake different parts of the unified programme, wherein full use will of necessity have to be made of data collected prior to the IGY. Thus, the British Meteorological Office has already done a considerable amount of work on the tabulation of global upper-air temperatures and presumably it may be willing to carry on and extend this analysis according to a previously defined and adopted plan. Other services will be responsible for other parts of the programme but much work of collation and filling in the gaps will have to be the responsibility of WMO. This is possible only if this body can command the services of sufficient qualified professional staff and this in turn requires adequate funds.

Comparing the WMO budget with those of some newly created United Nations agencies, one is struck by the almost incredible modesty of meteorologists all over the world. Perhaps modesty is all to the good but it would be an infinite pity if lack of (extremely modest) additional funds should prevent WMO from organizing a long overdue programme of international research.

T.E.W. Schumann

New British ocean weather ship

On 22 May 1958 a new British ocean weather ship, Weather Reporter, sailed on her first voyage to ocean station Alpha in the North Atlantic. Weather Reporter is a converted Castle class frigate and replaces Weather Explorer after over 11 years of strenuous service as an ocean weather ship. The Castle class frigates are somewhat larger than their predecessors and the accommodation is correspondingly more spacious and comfortable; they also have the advantage of a greater fuel capacity.

The meteorological office is situated on the upper deck aft, immediately forward of the balloon shelter. It is a bright and cheerful room lighted with four 21-inch portholes. The equipment includes two radiosonde receivers, a plotting table for upper winds, three mercurial barometers and a precision aneroid barometer, a distant-reading thermograph from the engine-room intake, a distant-reading psychrometer from screens on each side of the bridge and distant-reading anemometer and wind-direction dials from instruments mounted on a yard each side of the mainmast. For radiosonde reception a special aerial is mounted on top of the balloon shelter. A wave recorder connected to instruments located in the engine room and a recording potentiometer, which records total radiation and net flux of radiation from instruments mounted below the bridge, are also included. On deck is an electric winch for making bathythermograph observations and provision is made for other oceanographical work to be done.

Hydrogen stowage is provided on deck each side of the balloon shelter but for use in very heavy weather a few cylinders are kept inside the shelter. The balloon shelter is provided with a special ventilation system to obviate any risk of a hydrogen explosion and there are no electrical fittings of any kind inside it. Special wiring has been installed between the meteorological office and various points in the ship where experimental meteorological equipment may need to be installed, such as the bridge, masts and bow, so that special investigations can be carried out as necessary. The masts are provided with reasonably spacious platforms from which it will be possible to carry out experimental work aloft more easily.

The radio equipment includes a 10 cm radar, similar to that installed in the earlier ships, for making upper-wind observations to a height of 20 000 m, as well as for the provision of radar navigational fixes to aircraft in flight. A Decca 3 cm radar is also provided for the ship’s navigational purposes.

It is intended to replace the three other earlier British weather ships by vessels of a similar type to Weather Reporter in the near future.

News and notes

Death of Sir Gilbert Walker

It is with regret that we have learned of the death of Sir Gilbert Walker, C.S.I., F.R.S., on 4 November 1958 at the age of 90 years. Sir Gilbert was educated at St Paul’s School, London, and Trinity College, Cambridge, where his mathematical interests were mainly in the fields of dynamics and electromagnetism. It was only in 1903 when he became director-general of observatories in India that he became closely associated with meteorology.

Sir Gilbert will be remembered principally for his outstanding work in establishing correlations between meteorological phenomena in different parts of the world which formed the basis for his method of forecasting the course of the Indian monsoon. He was also responsible for initiating some of the early investigations into atmospheric electricity and the upper air. In 1924 he succeeded Sir Napier Shaw as professor of meteorology at the Imperial College of Science and Technology in London where he remained until his retirement in 1934. During this period he gave much attention to research work on the formation of clouds.

For more than 20 years Sir Gilbert also played a very active part in the work of the IMO. During much of this time he was a member of the International Meteorological Committee and also served on a number of commissions dealing with many different aspects of meteorology.

After a long and distinguished career which brought him many honours Sir Gilbert pursued his research work in retirement with as much enthusiasm as ever. On his 90th birthday he was reported to be collaborating in the writing of a textbook on the aerodynamics of the flute.

* An accidental release of radioactive material into the atmosphere which occurred at an atomic installation in the United Kingdom.

* This article is a personal contribution by T.E.W. Schumann, former director of the Weather Bureau of the Union of South Africa, and for many years actively interested in international meteorology.

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