When perils such as tornadoes or floods threaten the Springfield area, the modern version of a century-old hobby -- ham radio -- provides early warnings, timely tracking and even basic communications in the aftermath. Today's ubiquitous cell phones and internet access would seem to render civilian radio networks obsolete in emergencies, unlike in 1949 when a brutal ice storm crippled much of the Ozarks for a month. The thick ice brought down the Frisco Railway's telegraph lines, and hams used their radios to link depots. The same storm marooned the town of Stockton, with hams there connecting Cedar County residents and businesses with Springfield and beyond for almost a month. But nowadays funnel clouds can topple cell towers and disrupt computer networks, which happened in the devastating 2011 Joplin tornado, leaving ham operators to link Springfield hospitals with medical personnel whose facilities had been destroyed. Hams coordinated the dispatching of assistance to Joplin and the transfer of injured patients to Springfield.