The lava lake inside Halema‘uma‘u crater appears to have dropped by 6 feet in depth, the Hawaiian Volcano Observatory reported Saturday.
The eruption at Kilauea Volcano’s summit remained confined to Halema‘uma‘u with vents on the north and northwest sides of the crater feeding the lake, the observatory said. The crater lake, which was reported to be 577 feet deep Friday, appeared to have dropped 6 feet “leaving a narrow black ledge around the north edge.
Early Saturday, the west vent reactivated while the north vent quieted and started to drain the lake, according to the observatory. The lava lake volume was estimated to be about 27 million cubic yards or 4.8 billion gallons.
An island of cooler, solidified lava within the lava lake continued to get smaller and was drifting slowly northeastward in the lake. It remained about 850 feet in length and 375 feet in width.
The observatory noted along with the decrease in output from the north vent was reduced SO2 (sulfur dioxide) emissions. The rates appeared to drop from 35,000 to 40,000 tons per day to 16,000 to 20,000 tons per day.
Those emissions and other aerosols make up “vog,” or volcanic smog that’s typically across the Ka‘u District, hitting first areas like Pahala, Naalehu and Ocean View, before getting caught up in sea breezes that bring it toward West Hawaii and onshore in Kona.
According to the University of Hawaii at Manoa’s Vog Measurement and Prediction Project, northeasterly tradewinds were forecast to continue through Sunday, meaning vog may continue to impact areas southwest of the Kilauea summit caldera, including the western half of the southern coast of Hawaii Island (the Ka‘u District) and Kona.
Monday morning, the winds were forecast to become southeasterly, which should provide some relief from the vog for the Kona area as the winds push the vog northward toward the rest of the state.
For more information on the ongoing eruption, visit https://www.usgs.gov/observatories/hawaiian-volcano-observatory. For more information on vog, including ways to monitor air quality, visit https://vog.ivhhn.org.