Volcano news & updates: Kilauea volcano (Big Island, Hawaii)
Kilauea volcano update: How lava flow projections are refined
Friday Sep 12, 2014 22:33 PM | BY: PO
HVO's latest update:
"The flow front [yesterday at 12:30pm] was 14.8 km (9.2 miles) from the vent, measured in a straight line, and 0.3 km (0.2 miles) from the Forest Reserve/Kaohe Homesteads boundary. The actual length of the flow, measured along the lava tube axis (so that bends in the flow are considered) is 16.9 km (10.5 miles). Between September 6 and 10, the flow front advanced at approximately 400 meters (460 yards) per day. Between September 10 and 11 the advance rate dropped slightly to approximately 300 meters (330 yards) per day. The flow front is still in thick forest, creating smoke plumes as it engulfs trees and other vegetation, but fires are not spreading away from the flow."
The lava flow's turn to the northeast this week surprised many online observers, but was not as big a surprise to the scientists at HVO. The blue lines on HVO's flow update maps indicate the steepest downhill direction calculated from a digital elevation model obtained previously by satellite, but the satellite can't see the ground beneath the trees. These smaller hidden variations play a significant part in determining a lava flow's path, and in order to address that HVO scientists run simulations which introduce random variations of about 6 ft (2m) to the DEM surface. Then they compile a probability map based on those simulations. This technique was proven successful during a recent eruption of Mt. Etna, and is now collaboratively being used in Hawai'i. In fact, HVO's simulations earlier this week showed the current flow path as a good possibility given those random variations, but those maps have not been published online, only presented at the public community meetings.
The flow's speed has only decreased slightly as well, reflecting the steeper topographic slope of the area and giving the flow a long and narrow geometry. At present the flow width is reportedly 200-300m, which could restrict the lateral damage caused by the lava, at least in the short term. Looking ahead, the longer a lava tube system remains active, the more likely it will produce flows laterally, but for now there's no reason to believe the lava flow won't remain narrow as it builds downhill momentum towards the ocean. Along the same lines, there's no indication that the lava flow will slow down anytime soon and scientists now project it will cross the northern half of Pahoa and the highway around September 24-26.
In this iterative manner, HVO will continue to update its projections -- first mapping the new flow boundaries, then running new simulations based on that data. This is currently happening more or less every 2 days, and we will continue to report on any changes.
Friday, Sep 12, 2014
At the public meeting held at Pahoa High & Intermediate School last night, officials presented the latest lava flow maps and projections following the flow's unexpected turn towards Pahoa town two days ago. HVO scientists reported that the steep slope has allowed to flow to continue moving quickly and that the new path puts it directly through the town of Pahoa in the range of 13-15 days. ... [more]
Friday, Sep 12, 2014
HVO's latest warning status update issued yesterday: ... [more]
Tuesday, Sep 09, 2014
The latest updates from authorities show no significant change in the path of the lava flow, only advancement through the jungle away from houses, for now. ... [more]
Saturday, Sep 06, 2014
Lava flows continue to advance downhill through the jungle on a path that will miss Kaohe Homesteads, having first entered and overtopped several large ground cracks on Kilauea volcano's east rift zone. The farthest lava front is now 13.3 km (8.3 miles) from the vent and 1.2 km (0.7 miles) from the east boundary of the Wao Kele o Puna Forest Reserve, and moving northeast parallel to the boundary. ... [more]
Thursday, Sep 04, 2014
According to officials, the June 27th lava flow has reemerged for the second time from a huge ground crack along Kilauea's east rift zone, this time approximately 13.2 km (8.2 miles) from the vent and 1.3 km (0.8 miles) from the eastern boundary of the Wao Kele o Puna Forest Reserve, but still continues moving through the ground crack to within 1.1 km (0.7 miles) from the boundary. ... [more]