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Table of Contents
Glimpse of the RAAF Meteorological Service Preface Foreword Introduction Chapter 1: Growing Up Chapter 2: Port Moresby Before Pearl Harbour Chapter 3: Port Moresby After Pearl Harbour Chapter 4: Allied Air Force HQ and RAAF Command, Brisbane General Douglas MacArthur We Join Allied Air Headquarters, Brisbane Ralph Holmes Forecasting Procedure WAAAFs and Other Staff Briefing MacArthur & Co Domestic Affairs The Yanks Are Coming Japanese Advance Across Owen Stanley Range General George C. Kenney Additional Staff Staff Arrangements Long Range Forecast Investigations into Tropical Meteorology Radiosondes Analysis Statements MacArthur's Remarkable Strategy A New Direction Tropical Weather Research Bulletin RAAF Command, Pat Squires and Henry Phillpot Chapter 5: Japan Surrenders and We Are Demobilised Epilogue Acknowledgements Appendix 1: References Appendix 2: Milestones Appendix 3: Papers Published in Tropical Weather Research Bulletins Appendix 4: Radiosonde Observations 194146 Index Search Help Contact us |
Forecasting Procedure (continued)In our Allied Air Headquarters meteorological section we used the concept of air-masses and polar fronts as the basis of our routine synoptic analysis. The identification of air-masses was considered an essential component in frontal analysis and weather forecasting. Air-masses were identified by their assumed area of origin. Thus a 'polar maritime' air-mass was assumed to have acquired its characteristics (cold, moist) from the higher latitudes of the Southern Ocean. The characteristics of a 'tropical continental' air-mass (warm to hot, and dry) were assumed to derive from modification of air over arid regions of Australia. A 'tropical maritime' air-mass (warm, moist) derived its characteristics from modification of air over the ocean in latitudes from about 15 deg to 35 deg latitude while an equatorial maritime' air-mass (hot and humid) acquired its characteristic from the equatorial ocean.From today's perspective one may wonder why a more appropriate model was not used. It must be remembered that at that time our standard textbooks were those of Brunt and Petterssen, with the latter having the more practical usefulness for the weather forecaster. Petterssen's textbook devoted separate chapters to the subjects of air-masses and fronts. There was much to recommend the use of the polar front model for synoptic analysis and forecasting in latitudes poleward of 35 or 40 degrees and the identification of different types of air-masses was useful in weather forecasting. The 'front' was a useful concept in identifying and tracking long bands of cloud, usually associated with a wind shift and sometimes yielding rain, which usually moved to the north and east over the Australian continent and were highly significant in military operations. It was common practice to believe that the front could be 'active' (yielding cloud and rain) or 'inactive' (with no cloud or rain). The synoptic analyses of some meteorologists contained an array of parallel fronts from which any cloud or rain which occurred could be explained as the result of an active front, while if a front were not accompanied by cloud or rain it was regarded as 'inactive'.
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