To colleagues interested in jets, vortices & geophysical turbulence Richard Wood and I would like to call your attention to a preprint we've just submitted to J. Atmos. Sci, "A general theorem on angular-momentum changes due to potential vorticity mixing and on potential-energy changes due to buoyancy mixing". It clarifies, for instance, how the natural jet self-sharpening process causes jet cores to accelerate while reducing total angular momentum. Another spinoff is an extension of Arnol'd's first stability theorem beyond its original Hamiltonian framework. The preprint is available as a pdf at the hash link www.atm.damtp.cam.ac.uk/people/mem/#jet-sharpening-paradox or at www.atm.damtp.cam.ac.uk/people/mem/ after the string "may appear paradoxical". Please excuse any duplicates. As far as we are aware the results are not only fundamental but also novel. Comments welcome. Sincerely, Michael McIntyre *********************************************************************** Emeritus Professor M. E. McIntyre MAE FRS, Centre for Atmospheric Science at the Department of Applied Mathematics and Theoretical Physics, Wilberforce Rd, Cambridge CB3 0WA, United Kingdom Fax +44-1223-760419 and -765900 Tel +44-1223-337871, secretary -337870 (Loraine Knight) & +44-1223-363283, mobile/cellphone +44-794-786-0441 email [email protected], secretary [email protected] http://www.atm.damtp.cam.ac.uk/people/mem/#thinking-probabilistically *********************************************************************** _______________________________________________ discuss mailing list [email protected] http://www.atmosocean.org/mailman/listinfo/discuss
