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Hawaiian Volcano Observatory field crews establish a new MultiGAS volcanic gas monitoring station on the south side of Kīlauea Volcano's caldera. Currently, sulfur dioxide emission rates from the summit remain low. The station will collect data to track emission rates and concentrations over time. Photo by Frank Younger.
A close-up of the MultiGAS instrument (located in the tan box), which is placed in a larger black box to protect the instrument from the weather. The MultiGAS instrument collects an air sample and measures the concentrations of volcanic gases such as sulfur dioxide and carbon dioxide, as well as collecting data on environmental parameters like temperature and pressure. The instruments are typically placed at locations downwind of vents. The collected data is transmitted by radio to HVO, providing a record of changes in gas concentration that helps in understanding magma depth and the pathways by which gas reaches the surface. Photo by Frank Younger.