Methane seeps occur in locations where bubbles of methane gas, an important greenhouse gas, rise out from the seafloor. Multibeam sonar equipment aboard E/V Nautilus detects methane seeps by picking up on bubble streams emanating from the seabed. Along the U.S. Cascadia Margin alone, more than 2,700 new bubble streams have been discovered at over 1,000 individual sites in the last few years. These fountains of life power unique ecosystems home to some forms of bacteria that make food using chemosynthesis, a process that is comparable to photosynthesis but that uses methane instead of sunlight. The impact of methane seeps on our global climate is poorly understood. As such, there is great interest in the systematic mapping and characterization of methane seep sites to document their distribution, better understand their impacts on bottom and mid-water ecosystems, and to determine the current flux of methane into the ocean. Learn more: nautiluslive.org/science-tech