http://www.stormcam.org/gps-carry/
Would it make sense for all climbers to carry a kind of GPS device on every ride?
Only if they need to know where they are yet. A typical GPS tells the user where they are. It does not say where researchers are the users. If you think this is a device that allow researchers to know someone, then you talk about an EPIRB – an emergency locator radio or PLB – Personal Locator Beacon. These send a signal to satellites that can be transmitted to users. Boaters use RLS often, especially if they are in isolated sections of the ocean. PLB can locate a person normally within 2-3 miles. A-GPS enabled, you can get a lifeguard at least 100 meters, more or less.
New Program in Bryan Makes Truant Students Carry a GPS Device