July 29, 2026 — Sulfur Cone gas monitoring maintenance, Mauna Loa
July 29, 2026 — Sulfur Cone gas monitoring maintenance, Mauna LoaOn July 29, 2026, USGS Hawaiian Volcano Observatory gas scientists flew via helicopter to the Sulfur Cone Multi-Gas instrumentation site on Mauna Loa's Southwest Rift Zone, which is at an elevation of 3,430 meters (11,240 feet) above sea level.