THE WEATHER.

Auckland Star, Volume LXV, Issue 226, 24 September 1934, Page 9

THE WEATHER.

FORECAST PROBLEM.

WIRELESS REPORTS NEEDED. DEMANDS OF AVIATION. Mentioning the certain expansion of aeroplane services to and from New Zealand in the near future, the director of the meteorological branch of the Department of Scientific Research, in his annual report, stresses the need for the gathering of fuller information whereby to mafte more comprehensive weather forecasts. "The year has been remarkable for the number of times the Tasinan Sea has been successfully crossed by 'plane," the report says. "It seems certain that in quite a few years a regular transTasman service will be established. This will undoubtedly entail a meteorological service for aviation of quite a different character from anything which can at present be provided. On flying routes it; is necessary to know the weather in far greater detail than is required for other purposes, and frequent rapid collection and dissemination of information is an essential feature.

"The number of weather reports which can be got from the Tasinan Sea, and their distribution, depends entirely on the number and location of the ships crossing it. It can never be adequate, and frequently it is reduced almost to zero. This is one of the permanent drawbacks to weather forecasting in New Zealand. Nevertheless, this difficulty can bo overcome to quite a large extent if sufliciently complete reports be available from Australia. For these to be secured, the first essential is adequate facilities for communication by wireless.

"The reports received would bo extremely valuable in connection with the preparation of forecasts for general purposes as well as those for aviation. The need for increased wireless facilities has been referred to in previous reports. Nearly all important meteorological services now have stations of their own, and it is difficult to (see how satisfactory conditions can be reached in New Zealand, except by development on the same lines." The Norwegian Method. The director gives a brief resume of the Norwegian method of forecasting weather, a method which has gained approval practically over the world. The essential idea was that weather was due principally to the inter-action of "air masses'* of different characteristics! as regards temperature-, humidity and speed and direction of motion. Rainfall, for the most part, was produced by the forcing of warm air to rise in the atmosphere by colder, and therefore heavier, air masses. Warm air almost invariably contained more water vapour than cold. The enforced rise in the atmosphere led to the cooling of the warm air and to the condensation of some of its moisture in the form of rain. The forecaster consequently tried to define the boundaries of the different air masses, and the different reactions one on the other.

Norwegian's Help. "Fortunately for this branch," the report added, "an experienced Norwegian forecaster, in the person of Mr. Jorgen Holnvboe, was attached to the Lincoln Ellsworth Antarctic expedition: Mr. Holmboe has spent a considerable time at the meteorological office, Wellington, partly before the departure of the expedition and partly since its return. While here he has, in such time as was available, thrown himself enthusiastically into the study of local weather conditions, and, with the assistance of his special knowledge, it lias been possible to gain a much clearer insight into the methods used by his countrymen. Owing to New Zealand's isolation, this is not likely to lead to any revolutionary improvement in the weather forecast, but it will add greatly to the interest and understanding of weather processes. This is bound to produce a gradual increase of accuracy in forecasting. especially when it comes to the detailed work required for aviation purposes. For the method to be used successfully, however, we need, in addition to the Australian reports already mentioned, additional staff in order that reports may be charted as expeditiously as possible and the forecasting officer have time to consider tlie position fully and give proper attention to all aspects of the various forecasts required. The special forecasts asked for during the year indicate that very much increased attention is being paid by farmers to the weather forecasts in planning the day's work. Special mention may be made of warnings of approaching frost."