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Fifty years ago ...
From WMO Bulletin 5 (3), July 1956
picture on the cover
of the most important factors responsible for the recent
rapid advances in the science of meteorology is undoubtedly
the introduction of the radiosonde as a routine method for
measuring the pressure, temperature and humidity of the free
atmosphere. The importance of the pioneering results of the
early manned balloons last century, followed by the kites,
balloon meteographs and aircraft ascents in the first half
of the 20th century cannot be denied, but it was
only when upper-air data became available in large numbers
and from a wide network of radiosonde stations that
meteorologists were able to test out and improve their
theories of the atmospheric processes in three dimensions
and to apply them in their day-to-day analyses and
Less than 30 years have elapsed since the first radiosonde ascent was made in 1927 by Idrac and Bureau but in the meantime more than 50 different designs of radiosonde have appeared, of which perhaps 15 are now in routine use. The impossibility of satisfactorily comparing the accuracy of these instruments in the laboratory, owing to the difficulty of simulating flight conditions, has made it very desirable to organize international comparisons in which the instruments are flown in a manner similar to the routine soundings. The most recent, and by the most important, of these comparisons was carried out at Payerne, Switzerland, under the auspices of WMO, from 23 May to 15 June 1956. The picture on the cover illustrates various aspects of this work.
eighth session of the Committee was held at the Palais des
Nations, Geneva, from 17 to 30 April under the presidency of
Mr A. Viaut.
view of the widespread interest in the subject of the
International Geophysical Year, the decisions of the
Executive Committee were reported in a separate article.)
was clear that many of the new techniques employing
radioactive substances could be usefully applied to
meteorology, for example in devising improved instruments
for measuring depth of snow and soil moisture and in serving
as tracers for studying the movement of airmasses. WMO would
be called upon to play a dual role, first to advise Members
on the applications of these new techniques in meteorology
and secondly to assist other international organizations in
Committee also considered the question of the effect of
atomic explosions on the weather. There was no reason to
conclude that nuclear explosions had had any large-scale
effect on the weather.
One aim should be to achieve coordination of hydrological and meteorological work in all Member countries and, in parallel with this, for WMO to provide similar coordination at the international level. It was realized that the Organization was handicapped by not having a hydrometeorological expert on the staff of the Secretariat and the Secretary-General was requested to see what could be done as an interim measure to remedy this deficiency pending a review of the whole question at the next session of Congress.
of the most vital questions in international meteorology was
the improvement of the networks of meteorological reporting
Secretariat was preparing a series of regional charts
showing the existing and recommended networks for surface
and upper-air observations. The Executive Committee
recognized the usefulness of these charts and laid down the
broad lines for an expanded project, which provided for
regular distribution of the charts to Members and for the
institution of an amendment service.
overcome difficulties which had been experienced in the
past, an improved procedure was adopted for dealing with
recommendations arising from International Civil Aviation
Organization (ICAO) Regional Air Navigation meetings which
were referred to WMO for action in accordance with WMO/ICAO
President of Regional Association II (Asia) informed the
Committee that the present situation with regard to
in-flight reports from aircraft was not entirely
satisfactory in his Region, Similar views were expressed by
other members. These reports are of immediate use to
Meteorological Services in meeting the requirements of
and legal questions
Executive Committee had to deal with a number of legal
questions, such as the rules of procedure for the Committee,
possible revisions to the Convention and the implementation
by Members of resolutions and recommendations.
of the major items was the permanent building for the
Secretariat, which was still housed in temporary quarters.
An offer had been made by the Untied Nations to construct a
new wing to the Palais des Nations in Geneva to house both
WMO and the International Telecommunication Union, and the
Canton of Geneva had offered to erect either a special
building for WMO or an extension to an existing building.
The Executive Committee expressed preference for the Canton
proposal to provide a separate building for WMO and directed
the Secretary-General to continue negotiations with the
Canton authorities and submit details of the final scheme to
Members for approval.
Executive Committee expressed concern about the
difficulties in carrying out an adequate programme with the
present very limited funds. As the maximum expenditure for
the period 1956-1959 had been laid down by Congress, there
was little scope for varying the annual budgets from year to
year. The budget adopted for 1957 is therefore very similar
to the current budget, the total expenditure foreseen being
US$ 425 013.
year there was provision for financing meetings of one or
two working groups, and it was anticipated that a larger
number of groups might wish to meet.
The broad principle was that preference would be
given to small groups which had to deal with urgent
questions which could not be solved by correspondence.
had decided to establish an Operational and Technical
Development Fund amounting to US$ 9 600. The
Executive Committee decided to support two projects, namely
the trial period for the International Geophysical Year and
a radiosonde programme in Burma during the IGY.
Geophysical Year 1957-1958
meteorological problems to be investigated with the aid of
the observations made during the IGY related to the
large-scale physical dynamic and thermodynamic processes of
the general circulation. It was therefore essential that all
the Meteorological Services of the world should collaborate
both in carrying out the observations and in helping to make
the results readily available to research workers.
of the functions of WMO was to promote the establishment and
maintenance of systems for the exchange of weather
information. Hitherto, this work had been limited mainly to
the very important exchange of data needed for the
day-to-day operation of weather forecasting services. This
exchange would be continued during the IGY but it was not
considered to meet the needs of research workers who were
not so much concerned with the speed in obtaining the data
as in their accuracy and completeness. Many Meteorological
Services published their meteorological observations in the
form of daily, monthly and annual bulletins, but it was not
always easy for an individual research worker to lay hands
on copies of these publications and it was sometimes very
difficult to obtain the data he required from those
countries where no such publications exist. It should also
be remembered that there was considerable variety in the
layout and contents of these national publications which
increased the difficulties for certain types of
Executive Committee adopted a proposal whereby an IGY
Meteorological Data Centre would be established within the
WMO Secretariat. Meteorological Services would be asked to
supply their main IGY observations to this Centre on
standard forms (this would lead to a uniform presentation of
the data) and the forms would then be catalogued and
reproduced on micro-opaque cards.
would be four standard forms, one for the surface synoptic
observations from land stations, one for similar reports
from ships, one for combined radiosonde and radiowind
observations an the last for separate upper-wind
keep the amount of data to be handled within reasonable
proportions, the surface observations would be entered on
the standard forms would be limited to those at the four
main synoptic hours. The marine observations should include
all the ships which normally supplied weather reports, but
the land observations would only be requested from selected
stations. The basis of this selection was to provide a
sufficient grid of stations for the preparation of synoptic
charts on a hemispherical scale.
had been estimated that a complete set of IGY meteorological
data would require about 30 000 micro-opaque cards.
Each card would contain about 50 standard forms and each
form would contain up to 40 surface observations or four
radiosonde observations. It could be seen that the IGY
Meteorological Data Centre would have to handle material
amounting to many millions of observations.
total const involved in running the Centre was estimated to
be of the order of US$ 300 000.
Executive Committee decided that a trial period should be
organized from 6 to 10 January 1957.
was decided that, as far as meteorological codes and station
index numbers were concerned, the Antarctic would be treated
as a separate WMO Region for the IGY. The Committee also
agreed that degrees Celsius and metric units should be used
for all meteorological reports from the Antarctic; this
would be yet another step forward towards the achievement of
uniformity in meteorological units, which had so long been
one of the most desirable but most elusive goals of
Association VI (Europe)—second session
second session of RA VI was held in March 1956 in Dubrovnik,
Association was in favour of adopting the main synoptic
hours (0000, 0600, 1200 and 1800 GMT) for these observations
which were currently being made at the intermediate synoptic
hours (0300, 0900, 1500 and 2100 GMT). By deciding that all
countries in the European Region should release the balloon
carrying the instruments exactly one hour before the hours
of observation, the session took a new step towards the
standardization of upper-air observations.
network of stations making surface or upper-air observations
was examined in detail. For surface observations, a small
addition to the stations existing in the Region on 1 March
1956 was considered necessary to obtain satisfactory
was given to the introduction of a special new code (EXFOR)
for the exchange of temperature forecasts and to the
adoption of 150 and 100 mb as standard levels for upper-air
observations in the Region.
A plan for radio-teletype broadcasts to replace the
present Morse telegraphy transmissions
A reorganization of the broadcast schedule of North
Atlantic Ocean weather stations operated by European
countries. This reorganization provides for the successive
transmission by the five stations of their surface
observations with a delay of only two to eight minutes after
the hour of observations, their pilot-balloon observations
within 10 to 30 minutes and their radiosonde observations
within 25 minutes to one hour.
The development of experimental facsimile broadcasts,
the standardization of the apparatus and the characteristics
of the broadcasts.
A general review, which could be finalized during a
joint meeting with the International Civil Aviation
Organization, subject to their approval, of all European
meteorological broadcasts. In proposing this study, the
Association stressed that the present system for the
exchange meteorological data within the Region by Morse
telegraphy and the international network of teleprinters
allocated to meteorology was still insufficient to meet the
needs for meteorological information.
• Connection of the international meteorological teleprinter network of western Europe with the corresponding network of eastern Europe.
Association decided to carry out an investigation of the
standardization of instruments and the methods of
observations for hydrology and the preparation of
climatological maps for hydrologists. The meeting adopted a
project for a comparative study of the forecasting
techniques for high-level flights and suggested that a
special meeting of experts be convened.
A. Nyberg, Director of the Swedish Meteorological and
Hydrological Institute, was elected president and Mr M.
Perovic, Director of the Hydro-Meteorological Service of
Yugoslavia, was elected vice-president.
of sferics systems
comparison between thunderstorms observed visually or
aurally and those detected by different types of sferics
equipment in use in France, Great Britain and Switzerland
was carried out from 11 January to 11 February 1955.
first part of the report restated briefly the principles of
the equipment used and gave details of the methods and times
of observations for the period of the trials. A list of 13
European countries which had been asked to supply reports of
thunderstorms observe was also included, together with a map
showing the positions of the sferics stations employed for
the comparison and the area from which visual or aural
reports of thunderstorms had been received.
chief feature was the very small number of fixes reported by
both France and Switzerland and by both Great Britain and
Switzerland. This was attributed to the fact that thundery
zones were generally more numerous over sea than over land
in winter which meant that many occurred outside the maximum
range of 800 km up to which accurate fixes could be obtained
with the two Swiss stations.
The number of coincident fixes found by France and
Great Britain was substantially higher.
winter thunderstorm activity on the continent was generally
weak and of short duration the report concluded that the
cathode-ray direction-finding methods, in which readings are
made for only 10 minutes for each observation, gives a poor
chance of locating thunderstorms at this time of the year.
It also concluded that the fact that the narrow-sector
record did not record flashes outside the sensitive sector
resulted statistically in a decrease in accuracy. Most of
the thunderstorms occurring during the period of the
comparisons were not detected by the Swiss network because
they fell in the blind area.
was noted that the list of thunderstorms observed was
incomplete. Some countries included only those reported by
synoptic stations, which were too sparsely distributed to
represent the true amount of activity.
automatic rainfall stations
1952, the Central Meteorological Observatory of Japan had
installed automatic weather stations for rainfall,
consisting of 109 transmitting and 70 receiving stations.
Their purpose was to obtain prompt and immediate information
on rainfall in mountain regions were no observations could
be effected otherwise. Heavy rainfall, especially when
accompanied by typhoons, often caused destruction and
disaster in Japan. The need for urgent flood warning was
spring until late autumn the transmitting stations furnished
hourly UHF transmission of rainfall amounts (in mm) as
Morse-cope signals. Every hour the receiving stations tuned
their receivers and picked up the signals for onward
equipment consisted of seven units, i.e. the rain-receiving
unit, the metering unit, the coding unit, the programme-clock
unit, the transmitter unit, the power unit and the receiver
unit. The first six units constituted the manned
transmitting stations and the last unit was operated by an
observer at the receiving station. Each unit was portable.
operating principle was simple and straightforward.
The rainfall was caught by a funnel 14.14 cm diameter
with a wind shield, exposed on the roof of the transmitting
station hut. The metering unit was a tipping-bucket system
which incorporated a mercury switch. The instantaneous
electric pulse, triggered by the mercury switch,
corresponding to each bucket turnover (1 mm rainfall),
energized an electromagnet in the coding unit and set the
position of three Morse-code cylindrical templates. The
templates could compose three numerals of rainfall amount
from 000 to 999 mm, after which they returned to 000 mm
again. A sliding key travelled along the templates,
call-sign first, and interrupted the plate current of the
transmitter unit. The plate voltage was stepped up by a
motor-driven vibrator from a stack of air wet cells of the
power unit, which also provided the electric power of the
time keeping and control of the whole programme was effected
by the programme-clock unit.
receiving unit was a standard type receiver with ancillary
equipment similar to that employed in the Japanese
radiosonde system. The Morse-code signals are heard as
audiofrequencies corresponding to the frequency of the
of their increasing reliability and ease of maintenance, the
value of the instruments in the rainfall observation network
of Japan was becoming fully recognized.
Humid tropics research
of specialists, 22-24 March 1956 in Kandy, Ceylon, preceded
by a symposium on tropical vegetation, in collaboration with
Increased knowledge of these climatic regions resulting from a carefully planned programme of research could appreciably assist the solution of problems affecting human settlement and economic development in the humid tropical zone.
meeting considered that fundamental research in all
scientific aspects was of the utmost importance and
recommended the creation of a permanent committee to advise
on all problems within the scope of the natural sciences in
humid tropical zones.
attention was paid by the meeting to the meteorological
aspects of most of the problems dealt with and to the
meteorology and climatology of the humid tropics.
of papers on tropical vegetation were urged to provide, for
the area of study, mean monthly temperature, mean annual and
monthly rainfall and mean monthly maximum and minimum air
humidity. It was further recommended that a symposium should
be organized to coordinate the aims and methodology of
vegetation, climate and soil studies in the tropics. The
symposium also proposed that Meteorological Services should
be encouraged to keep records of temperature and atmospheric
humidity and other data of interest to ecologists and that
records should be started in regions which were
was felt that there was often a failure to make full use of
existing meteorological data and that the special
requirements for research were not always brought to the
notice of the meteorologists who might be able to help them.
simple delineation could be made between the arid and humid
tropical zones but it would be useful to draw a boundary
between the two on a small-scale map. The possibility of
dividing the humid tropical zone into subzones should also
Suggested topics for inclusion in the UNESCO Humid Tropics Research Programme were:
awards to Australian selected ships
A system of Excellence Awards to Australian weather reporting ships was instituted by the Bureau of Meteorology as a means of giving concrete recognition of the cooperation of ships’ captains and officers in the provision of daily weather reports on a voluntary non-allowance basis. This action was taken in pursuance of the resolution adopted at the 1955 Conference of Commonwealth meteorologists in London, recommending the practice of making awards to selected ships which consistently maintained a high standard in their weather observations and reports.
Excellence Award would be limited to cases in which a high
standard had been maintained in the performance of
meteorological observations, the maintenance of a weather
log and the transmission of regular reports over a minimum
period of five years.
of the award emphasized the importance placed by the Bureau
of Meteorology on ships’ reports received not only from
Australian waters but also from the Indian, Pacific and
South Ocean areas and its desire to encourage ships’
captains and officers to report as regularly and accurately
as possible. It was gratifying to note the increasing number
of reports being received from selected ships.
were being received from 27 ships comprising the Australian
reporting fleet, of which 16 were of Australian and 11 of
overseas register. Since many of the ships of the Australian
register were practically wholly engaged in the coastal
trade, it was uneconomic to recruit and equip them as
selected ships but every opportunity was taken to encourage
all ships to report during storm and cyclone.
spite of the increased attention given to it by scientific
expeditions in the 20th century, Greenland
remained one of the largest and least explored landmasses to
challenge the resources of man. The long history of
Greenland exploration which began a thousand years ago must
have been uppermost in the minds of the scientists of eight
countries who met at Grindelwald and the Jungfraujoch
Research Station, Switzerland, from 3 to 8 April 1956 to
plan the scientific programme and organization of a new
expedition, the International Glaciological Expedition to
it did not form part of the official programme arranged for
the International Geophysical Year (IGY), the work of the
expedition would be coordinated with the IGY programme.
Investigations would be made in the sciences of meteorology,
glaciology, geophysics and geodesy. Study groups would work
both on the coasts and the ice-cap and the expedition was
expected to be in the field from 1957 until 1960.
Two or three meteorological stations would be
established to study especially the lower layers of the
atmosphere up to about 300 m above the surface of the névé
and the problem of snowdrift.
the Viking, Eric the Red, had established settlements in
Greenland before the end of the 10th, little was
known of the country before the English navigator Martin
Frobisher landed there in 1578. The work of exploration
which he initiated was continued by famous explorers such as
Davis, Hudson and Baffin in the 17th century and
by Danish settlers at Godthaab in the following century.
the 19th century the mapping of the coastal areas
was almost completed by Danish, English, American and German
expeditions and a start was made on the exploration of the
ice-cap which had hitherto prevented any attempt to reach
the interior. This enormous ice-sheet, five times the area
of France, covers the whole of Greenland apart from the
coastal regions and constitutes the largest glacier in the
northern hemisphere. It rises to a general level of 3
000 m and is believed to have a depth of 2 000 m in
central Greenland from which it flows slowly outward to the
coats. If melted, the mass of water released would be
sufficient to raise the level of the sea by more than 7 m
throughout the world.
Danish explorer Jensen was the fist to make notable progress
across the ice-cap when he reached a height of 1 700 m in
1878. In 1886, Peary and Maigaard reached a point 160 km
inland, 2 300 m above sea level. Two years later, Nansen
made the first complete crossing of the ice-cap from east to
west. A second crossing was made by Peary and Atrup in the
course of an expedition which determined the northern limit
of the ice-cap.
founding of a station at Thule by K. Rasmussen in 1910 began
an intensive period of exploration of northern Greenland by
Denmark. Five expeditions under Rassummen and Koch used
Thule as a base and Peary fitted out his polar expedition
there. In later years it was to become an important link in
a chain of Arctic weather stations.
crossings of the ice-cap by the Swiss, A. de Quervain and by
Koch and Wegener marked the progress of 20th
century Greenland exploration. By 1931 Germany had become
the first country to make a crossing by air. In the same
year, a British expedition under Gino Watkins made weather
observations from the ice-cap beyond the Arctic Circle,
whilst a German expedition led by Wegener wintered 300 miles
further north. Since the Second World War, both French and
British expeditions had established stations on the ice-cap
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