Cell phone towers can do more than just satisfy our need for constant communication; they might be able to save us from major floods, according to researchers from Tel Aviv University. Professor Pinhas Alpert and colleagues report in the April 2009 issue of Atmospheric Chemistry and Physics that they have figured out a way to exploit the phenomenon of atmospheric humidity influencing radio signals to provide information about "critical moisture distribution" levels that predict big floods.
The researchers used data from two Israeli cellular providers to show how microwave links in a cell phone network correlate with surface humidity. By monitoring moisture levels near multiple cell phone towers, the researchers were able to detect anomalies that could hint at future floods. In a post-analysis of two floods in Israel's Judean Desert, Alpert and team found that they could estimate the size of the disasters before they happened when moisture information was combined with rainfall distribution measurements.
Now that the formula for flood prediction has been proven, Alpert plans to bring his cell phone tower technology to the U.S. grid. It should be easy to implement since cell phone providers already collect moisture data to keep communication quality high no matter what the humidity level. If the Tel Aviv team's discovery works in the real world, it could prevent false alarms that leave residents of flood-prone areas jaded by the time forecasters make legitimate warnings.