“A massive ash plume rising from a fissure on Hawaii’s Kilauea volcano has caused authorities to issue a red alert for airplanes in the region for the first time since the mountain suddenly ramped up its activity nearly two weeks ago.
What scientists have dubbed ‘vog’ – a combination of volcanic gas and ash reached 12,000 feet into the sky above Kilauea — one of the world’s most active volcanoes.”
Source: Red Alert Issued For Aviation As Kilauea Spews ‘Vog’ 12,000 Feet Into Sky : The Two-Way : NPR