This week's guest WeatherBrain is a writer, navigator and an explorer.  He is the Sunday Times bestselling author of "The Walkers Guide to Outdoor Clues and Signs",  one of the world's only books related to natural navigation.  He's written for Sunday Times, New York Times, and the BBC.  He recently wrote a book called "The Secret World of Weather".  Tristan Gooley, welcome to WeatherBrains!