1600-1750 1750-1815 amériquedunord biographies biography canada canada(est) changements chefs climat climaticchanges eastern emergencymanagement gestiondessituationsd'urgence guerres histoire history icestorms indiansofnorthamerica indiens indiensd'amérique kingsandrulers leadership newengland planification planning tempêtesdeverglas unitedstates wars états-unis