What's happening at Kīlauea Volcano's summit vent?
Release from USGS/HVO

Webcam images of Kīlauea Volcano's summit vent on May 8, 2015 (left), and May 12, 2015 (right), show the 23 m (75 ft) drop in the lava lake level that occurred during that time.
Webcam images of Kīlauea Volcano's summit vent on May 8, 2015 (left), and May 12, 2015 (right), show the 23 m (75 ft) drop in the lava lake level that occurred during that time.

What a difference a few days can make on Kīlauea! On May 8, 2015, the summit lava lake reached its highest level to date—8 m (26 ft) above the original floor of Halemaʻumaʻu Crater. This was possible because multiple overflows and spatter from the rising lake built a ridge (levee) of solidified lava around the vent, forming a “perched lava lake.”

But on May 9, the lake level began to drop in response to a switch from summit inflation to deflation. By the morning of May 12, the lava lake level was about 15 m (50 ft) below the original floor of Halemaʻumaʻu Crater.

Rates of tilting recorded at Kīlauea's summit continued to slow down and have leveled off over the last 24 hours. Seismicity rates in the summit area and upper southwest rift zone are still elevated above normal levels, but have decreased in the past two days. The summit lava lake level held steady at about 50 meters (165 feet) below the original crater floor. Sulfur dioxide emission rates averaged 3,400-6,900 tonnes/day for the week ending May 12.

HVO scientists are closely monitoring the summit vent, and changes in the lava lake level are posted in HVO's daily Kīlauea eruption update.

Background information about this ongoing eruption is provided in “The first five years of Kīlauea's summit eruption in Halemaʻumaʻu Crater, 2008-2013.”

The active vent (Overlook crater) at the summit of Kīlauea Volcano is located within Halemaʻumaʻu, a crater within the volcano's caldera.  The lava lake within the summit vent was about 70 m (230 ft) below the vent rim when this aerial photo was taken on March 6, 2015.  Hawaiʻi Volcanoes National Park’s Jaggar Museum is perched on the Kīlauea caldera rim (out of view to the right).
The active vent (Overlook crater) at the summit of Kīlauea Volcano is located within Halemaʻumaʻu, a crater within the volcano's caldera. The lava lake within the summit vent was about 70 m (230 ft) below the vent rim when this aerial photo was taken on March 6, 2015. Hawaiʻi Volcanoes National Park’s Jaggar Museum is perched on the Kīlauea caldera rim (out of view to the right).