30 Dec, 1910.] Australian Meteorology and Weather Forecasting. 769 



SOME XOTES ON AUSTRALIAN 31ETE0R0L0GY AND 

 WEATHER FORECASTING. 



H. A. Hunt, Commonzcealtli Meteorologist. 



The continent of Australia, by reason of its insularity, geographical 

 position, and absence of extreme physiographical features, is freer from ex- 

 tremes of climate and violent wind experiences than any of the others. 

 There is not, therefore, the occasion here for the elaborate system existing 

 in America for giving warning of blizzards and of the devastating floods 

 which occur in its mammoth rivers, nor is it necessary to have the extraor- 

 dinary cyclone warning system of the Indian Meteorological Service. 

 Nevertheless, we have our weather troubles, though they be of a character 

 less se\ere than those of may less favoured countries. 



Australia lies in the path of what is known as the dry southern anti- 

 cyclonic belt, i.e.. the region of high barometric pressure lying between the 

 regions of the south-easterly and the westerly trade winds of the southern 

 hemisphere. 



If the course of this high pressure (which is composed of immense anti- 

 cyclonic links) were uniforml\ regular both in latitude and daily rate 

 of progression, our continent would undoubtedly be dry and arid, and 

 forecasting of the weather would be very simple, but, fortunately for 

 Australia, the movements of those anti-cyclonic links when traversing 

 Australia are erratic, and swing to and fro between the equator and the 

 South Pole, thereby bringing the equatorial and antarctic low pressure belts 

 with attendant and abundant rains alternately o\"er southern and northern 

 parts of the continent. The north-eastern half of Australia mainly 

 benefits from the equatorial intrusion during the summer months and the 

 south-western half, i.e., roughly, south of a line joining Geraldton, in 

 Western Australia, and Cape Howe, on the New South Wales coast, from 

 the Antarctic intrusion during the winter months. Farmers and pastoralists 

 may, therefore, reasonably look for their best seasonal rains according to 

 the relation of their holdings on or near to this line. 



It is regrettable that, owing to the infancy of the science of 

 meteorology, together with the complexity and the evasiveness of the sub- 

 ject, no law in any part of the world has yet been established that will 

 justify reliance being placed upon seasonal forecasts. The value of such 

 forecasts is of the greatest moment to the future of Australia in particular, 

 and many lines of investigation are being undertaken for the solution of 

 the problems involved, with the hope of success in the no distant future. 

 Meanwhile, the Australian .service is doing its best in the issuing of 24 to 

 48 hours' forecasts, and, at tim.es, even for longer periods, with a fairly 

 high percentage of accuracy. 



These forecasts, if a\-ailed of, should be of value in the following 

 ways : — 



Wool scouring, drying preserved fruits, salt manufacturing, and like 



industries depending upon an out-door exposure. 

 To the farmers and pastoralists as a guide as to when to sow and 

 reap ; the housing of sheep during the shearing season to a\oid 

 waste of time and money owing to the liability of wool getting 

 wet ; the repair of decaying shelters when violent winds are 

 threatening ; the conveyance of stores to and produce from farms 

 to railway stations, which depend upon a good condition of 

 roads ; the remoA'al of stock from areas likely to be flooded. 



