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Table of Contents

Memories of the Bureau, 1946 to 1962





Chapter 1: The Warren Years, 1946 to 1950

Chapter 2: International Meteorology

Chapter 3: The Timcke Years, 1950 to 1955

Chapter 4: A Year at the Massachusetts Institute of Technology
Melbourne to Cambridge, Massachusetts
Long-range Forecasting
Synoptic Meteorology
Dynamic Meteorology I, II, III
Dynamic Meteorology IV
Physical Meteorology
Audrey Joins Me in Boston
Was it Worthwhile?

Chapter 5: The Dwyer Years, 1955 to 1962

Chapter 6: A Springboard for the Future

Appendix 1: References

Appendix 2: Reports, Papers, Manuscripts

Appendix 3: Milestones

Appendix 4: Acknowledgements

Appendix 5: Summary by H. N. Warren of the Operation of the Meteorological Section of Allied Air Headquarters, Brisbane, 1942–45



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Dynamic Meteorology IV (continued)

My notes on Lettau's lectures occupy more than 50 pages containing many mathematical expressions and equations relating, among other things, to the statistical theory of molecular motion which Lettau believed could be used in the study of motions on a larger scale. They also contain discussions of random motion, concepts of viscosity, conduction of heat, molecular diffusion. Maxwell's transfer equation, various formulae for indices such as Richardson's number, Ekman spiral, the heat budget and associated topics.

I found his lectures challenging and stimulating. I had often wondered about the influence of frictional forces on motion of the air, especially in low latitudes, and even had the temerity to make some of my ideas the subject of my first paper published in a scientific journal.

Lettau revealed the great complexity of the subject and made me question my simple assumption in that paper that the friction force in equations of motion could be a function of mean wind speed and altitude above ground level.

I retained little of the detail of Lettau's lectures for it had little relevance to the areas of meteorological research in which I was interested. But I enjoyed his lectures because of the immense breadth of his vision. One quotation made during his lectures made a profound impression. It was his enunciation of the principle of d'Alembert (1717–1783) which my notes record as "if it happens that a question which we wish to examine is too complicated to permit all elements enter into the analytical relation which we wish to set up, we separate the more inconvenient elements, we substitute for them other elements less troublesome, but also less real, and then we are surprised to arrive, notwithstanding our painful labour, at a result contradicted by nature".

It might be useful for the developers of computer models of the atmosphere to take note of that quotation.

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Gibbs, W. J. 1999 'A Very Special Family: Memories of the Bureau of Meteorology 1946 to 1962', Metarch Papers, No. 13 May 1999, Bureau of Meteorology

© Online Edition Australian Science and Technology Heritage Centre and Bureau of Meteorology 2001
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