Affiliation: | School of Mathematics and Statistics, University College, The University of New South Wales, Australian Defence Force Academy Canberra ACT 2600, Australia e-catchpole{at}adfa.oz.au Institute of Mathematics and Statistics, The University of Kent at Canterbury Canterbury, Kent CT2 7NF, U.K. B.J.T.Morgan{at}ukc.ac.uk Institute of Hydrology Maclean Building, Crowmarsh Gifford, Wallingford, Oxfordshire OX1 0 8BB, U.K. snf{at}mail.nerc-wallingford.ac.uk |