Cambridge Summer School in Geophysical and Environmental Fluid Dynamics

"Fundamental concepts and processes" -- supplementary materials

M. E. McIntyre

This web page gives access to material I used to hand out during my Summer School lectures on "Fundamental concepts and processes", every year since the early 1990s up to 2006. The first Summer School was held in 1991. The material was transferred to the web in 2005. Also, some of the flavour of the lectures themselves is now accessible in the web version of this lecture for atmospheric chemists given at the September 2005 Seminar of the European Centre for Medium Range Weather Forecasts and based on the Summer School core lecture material. (I have degraded the quality of the slides and default movie to keep file sizes small.)

Here are the notes referred to in the lectures as Appendix I: on the `counterpropagating Rossby waves' mechanism underlying the commonest shear instabilities, barotropic and baroclinic. These are ubiquitous in fluid flow on large and small scales and basic to understanding eddy motion in the oceans and atmosphere. The ideas go back to the work of G. I. Taylor, James Lighthill and Francis Bretherton. They have been further developed in a series of papers by former summer school student Eyal Heifetz and various collaborators, of which a recent example is Heifetz, E. and Methven, J. (2005). `Relating optimal growth to counter-propagating Rossby waves in shear instability', Phys. Fluids, 17, 064107.

Here is a scanned pdf (1.6 Mbyte) of my 1993 review Isentropic distributions of potential vorticity and their relevance to tropical cyclone dynamics. This was Appendix II of past handouts. It was written for the proceedings of the UN-sponsored Beijing Symposium on Tropical Cyclone Disasters, and supplements the big 1985 review about isentropic maps of potential vorticity with Brian Hoskins and Andy Robertson -- the one in Quart. J. Roy. Meteorol. Soc. in which we weren't careful enough to attach the word isentropic to the word distributions. See also the Corrigendum and supplementary remarks to that review published in 1987, and my article on the concept of potential vorticity and its history in the Encyclopedia of Atmospheric Sciences. The famous PV Song (with rather clever lyrics by Nick Hall and John Thuburn and complete with authentic guitar chords) can be found at the website of the 2006 Chapman Conference on Jets and Annular Structures in Geophysical Fluids. The tune is the Beatles' Let It Be. At the last Summer School in September 2006 we performed a grand classical choral version, including homage to Beethoven and Carl Nielsen. More seriously, here's the new general theorem with Rich Wood on the implications of PV inversion for jet self-sharpening now published (2010) in J. Atmos. Sci; see also a short article in ADGEO (Advances in Geosciences) reviewing other fundamental advances including the hyperbalance equations (.pdf, 0.1 Mbyte).

Here is the big review article referred to in the lectures as Appendix III: Atmospheric dynamics: some fundamentals, with observational implications. It came out of the 1993 Enrico Fermi School held at the Villa Monastero, Lake Como.    Section 11, p. 36 ff., gives a careful discussion of the various incompatible uses of words like `source' and `sink' in the literature -- particularly as regards the analogy between the Rossby-Ertel potential vorticity on the one hand, and the mixing ratio of a chemical constituent or of electric charge on the other. Section 6 contains what I think is a nice counterexample -- under the heading `polar cooling thought-experiment' (p.14) -- to the myth that the stratospheric Brewer-Dobson circulation is driven by solar heating, in which connection see also the abovementioned lecture for atmospheric chemists.

Here is a shorter review written for the European Space Agency, referred to in the lectures as Appendix IIIa. It includes discussions of "gyroscopic pumping" and the "atmospheric tape recorder".

Here are the lecture handouts giving a summary of the most basic equations used in fluid dynamics, a summary of dimensionless parameters used in fluid dynamics, and some typical numerical magnitudes, such as the natural replenishment rate of stratospheric ozone, ca. 3 million tonnes per day. As Lord Kelvin famously said, I have no satisfaction in formulas unless I feel their numerical magnitude.

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This page first posted 2005; last updated 30 May 2011
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