UNIFORMITY NEEDED

Evening Post, Volume CXXVIII, Issue 53, 31 August 1939, Page 5

UNIFORMITY NEEDED

IN WEATHER DATA

METEOROLOGICAL PROGRESS

The annual report of the Meteorological Office, after commenting on the further expansion of the service necessitated by the accelerated development of civil and military aviation, remarks that conditions have in many ways been difficult owing to the need to train so many freshly appointed officers at the same time. "As soon as one officer has mastered the rudiments of any branch of the work he has had to make way for another. It will, naturally, be some years before the new staff can reach full efficiency. In the meantime, an added burden is placed on those who have had more than a year or two's experience. It is particularly difficult for the forecaster, who is unable to have the daily weather chart to himself for any long period, and so to make his own analysis and to keep in close touch with the changes from one chart to another. On the other hand, the additional reports received have been of considerable assistance to the forecaster."

The need for uniformity in the methods of making and recording meteorological observations, and of coding them into weather reports for transmission to forecasting centres, is stressed in the report. "The only way," says the report, "in which a meteorologist can understand the existing situation and so anticipate future changes is to plot the information received on charts so that it can be taken in by the eye, and the relation of the different elements grasped. He has to. form a mental picture of the state of the weather over a very wide area. If reports come in different codes, if different elements are reported, or different units used, the difficulty in charting is very much increased. Not, only that, but aviators pass rapidly from one country to another and the charts used in different centres must be intelligible to them. The same applies to a somewhat lesser degree to mariners. The methods of plotting reports and drawing maps must, therejfore, also be uniform. The charts themselves must, be on uniform and suitable projections and the number of different scales reduced to a minimum. To meet all these needs very full regulations have been laid down by the International Meteorological Organisation and are revised from time to time as experience dictates. There is no means of forcing countries to adopt the procedure recommended by the international Meteorological Organisation—the only compulsion arises from the obvious advantages of doing so. In recent years it *has been the practice of the New Zealand Meteorological Office to conform as nearly as possible with international rules. This has greatly simplified the collection of in- j formation from other countries and ships at sea. It also enables New Zealand meteorologists to read the charts of other countries which follow the same practice with the minimum of difficulty. At the same time, people from the Northern Hemisphere can follow our charts as if they were thenown. The need for uniformity of this kind becomes extremely important amongst allied nations in war-time, when operations are so largely affected by the weather. It means that practically no difficulty is experienced from differences of language or social organisation. THINKING IN MILLIBARS. "One of the results of the international organisation of weather reporting has been that all issues of collected weather reports by radio are in international codes. These are used by the various weather services and by ships at sea. According to these codes airpressure is always given in millibars. The millibar has been in use in most European countries for many years. In England it was introduced before the Great War. Gradually it is being brought into use by countries all over, the world. The millibar is 1000 dynes per square centimetre and so expressed in terms of force units. It is, therefore, a much more logical unit of pressure than the artificial one of the inch or millimetre of mercury. If the millibar is to be the official unit, it is most desirable that everyone should think of pressure in millibars. It is therefore equally desirable that other units should be dropped, especially just now, when so many people are taking up the study of meteorology for the first time in connection with aviation. In the future, therefore, all reports and publications from the New Zealand Meteorological Office will give pressure in millibars. Many other difficulties would be removed if Englishspeaking countries could be induced to adopt the metric system for all purposes. "The past few years have seen a very great intensification of the application of scientific methods to the organisation of all forms of business and production. This has necessitated much more precise study of all the factors involved. The influence of weather on so many activities has, consequently, been brought forcibly to the notice of those planning them. With this has come the realisation that the weather must be studied scientifically if proper use of, or allowance for, it is to be made. The demands for advice, information, and equipment have thus grown at an unprecedented rate and it has been difficult to keep pace with them."