In the normal (low power) mode, the BPR reports every hour to the buoy water and transmits column
height values for 15-minute intervals during each 1-hour period. The buoy then transmits the data via
Iridium satellite communications every 6 hours in the normal or low-power mode. Upon activation of the
tsunami mode, the BPR alerts the communications buoy of the detected event. The buoy then
immediately transmits the received high resolution 15-second water column height data to the warning
center. Following the initial event mode transmission, the system continues to transmit specific eventrelated
water column data, in a preprogrammed time scenario, over the next 3 hours, after which, the
system returns to the normal mode.