An impact sound source useful for Arctic remote sensing

The impact on an ice surface of an energetic projectile, such as a rifle bullet, which creates an acoustic impulse in the water whose properties are useful for Arctic remote sensing, is discussed. The source level of these impulses is typically between 220 and 230 dB Re 1 mu Pa at 1m and most of their energy is within the band 500 Hz to 3 kHz. Possible remote sensing applications are reviewed together with available experimental data. These include the measurement of ice properties and water depth, as well as bottom imaging. It is concluded that the source described has potential for Arctic acoustic remote sensing applications where probability and ease of deployment are important and the required number of measurements is not too large. >