Used to explore the geologic structure below the ocean floor, seismic airguns produce "explosions" of air at regular intervals. This explosive release of air can create source amplitudes up to 240dB. The PMEL autonomous hydrophone array deployed in the central Atlantic Ocean recorded at least three different airgun sources from around the Atlantic Basin, sometimes simultaneously. The most frequent origin locations were near Nova Scotia, Canada, Northeast Brazil, and Northwest Africa. Airgun signals dominate approximately 75% of the annual data recordings.