Page:Types of Australian weather.djvu/5

 TYPES OF AUSTRALIAN WEATHER.

By ,

Second Meteorological Assistant, Sydney Observatory.

[With Forty Diagrams.]

continuation of the valuable work on Australian Meteorology which the Hon. Ralph Abercromby initiated several years since, by offering a money prize for the best essay on Southerly Bursters; he has recently selected the phases of Australian Weather which are treated in the following twenty studies of "Types of Australian Weather." Many of these appear to be peculiar to Australia, and at the same time connected with Equatorial and other weather. That they throw much new light upon the source of the greater part of Australian rain, and show how these rain storms develop out of ordinary weather conditions is certain; at the same time they form an important contribution to the study of weather in the Southern Hemisphere generally. The work has been done by Mr. H. A. Hunt, at Mr. Abercromby's expense, and Mr. H. C. Russell, has edited the work.

As a general rule, weather is set fine when anticyclones move rapidly, and in a straight line across Australia, i.e., at a rate exceeding five hundred miles per day. And weather is unsettled when they move slowly, and not in a straight line, i.e., in a zigzag line, especially if they show no appreciable forward motion for a day or two. When anticyclones move in low latitudes the conditions favour dry weather, in high latitudes, wet weather, especially if they rest for a time south of South Australia.

All the examples of weather phases which follow have been selected from the Sydney Weather Charts, and illustrate each type. The originals were carefully traced, and then reduced from 22" x 17" to the size used in this essay by means of the camera.

Gg—Dec. 4, 1895.