PHOTOGRAMMETRIC ENGINEERING & REMOTE SENSING
December 2018
751
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INSIGHT:
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utes, rapid turnaround times allowed for a regular presence in
the air. Their observations provided critical situational aware-
ness for ground crews working in proximity to the flow fronts
and for Hawai‘i County Civil Defense officials who were respon-
sible for emergency response. The UAS were able to collect im-
agery for orthophotos and digital elevation models (DEMs), as
well as volcanic gas emission measurements over the flow field.
In doing so, the UAS supplied monitoring data and updated
topography for lava flow hazard assessments during the erup-
tion, but these data will also constitute the basis of numerous
research projects in the coming years. Of particular significance
are the hours of nadir-looking video at pre-designated velocity
measurement points in the lava channel from fissure 8 (Figure
2), which will allow unprecedented detail in calculating lava
eruption rates and understanding channel dynamics. UAS were
also successful in repeatedly imaging the collapsing Kīlauea
summit with high-resolution cameras, enabling the creation of
DEMs to track topographic changes there.
After erupting for over three months, destroying over 700
structures, and covering 35.5 square kilometers of the Island
of Hawai’i with fresh lava, the eruption rapidly wound down
between 4 and 5 August 2018. For several days from the end
of August to the beginning of September, lava briefly returned
to the fissure 8 cone and was again monitored by UAS, before
subsiding and leaving a deep, quiet pit where molten rock
once fountained more than 60 meters into the air. However,
the remote sensing mission is not complete, and may just be
getting started. Lidar surveys over the entire subaerial flow
field will be used to produce post-eruption DEMs; compar-
isons with pre-eruption models will constrain the total vol-
ume of lava erupted. In addition to the local UAS surveys,
larger lidar surveys completed during the eruption in June
and July provide benchmarks to track growth of the flow field
over time. Additionally, offshore sonar surveys by the Ocean
Exploration Trust – using the research vessel
Nautilus
of the
Woods Hole Oceanographic Institution – will allow similar
quantification of the volume of lava sent into the ocean.
Without a doubt, remote sensing tools were critical compo-
nents of the 2018 eruption response, providing input for haz-
ard assessments in near-real time and producing world-class
datasets for continued study. High-resolution satellite data,
thermal imagery from helicopter and satellite platforms,
structure-from-motion software, UAS, and lidar have brought
high precision and speed into mapping that now encompasses
three dimensions. The 2018 Kīlauea eruption response ful-
ly utilized these emerging tools and provides a template for
remote monitoring of hazards and processes associated with
effusive eruptions, as well as caldera collapses, in the future.
Among the challenges going forward will be processing and
storing the vast volumes of data from an increasing number of
remote sensing platforms and tools, while the ability to rapidly
acquire, analyze, disseminate, and archive data will require
new approaches to data management and visualization.
A
uthors
Michael Zoeller
,
, is a GIS Specialist
with the Center for the Study of Active Volcanoes at the
University of Hawai‘i at Hilo.
Matthew Patrick
,
has been a Research
Geologist with the U.S. Geological Survey’s Hawaiian Volca-
no Observatory since 2007, focusing on eruptive processes at
Kīlauea Volcano.
Christina Neal
,
has been the Scien-
tist-in-Charge at the Hawaiian Volcano Observatory since
2015, and previously served 25 years at the Alaska Volca-
no Observatory, where she studied Aleutian volcanoes and
helped to develop an interagency eruption response system.
B
ibliography
1 Tilling, R.I., Kauahikaua, J.P., Brantley, S.R., and Neal,
C.A., 2014, The Hawaiian Volcano Observatory—a nat-
ural laboratory for studying basaltic volcanism, chap. 1
of
Poland, M.P., Takahashi, T.J., and Landowski, C.M.,
eds., Characteristics of Hawaiian Volcanoes: U.S. Geo-
logical Survey Professional Paper 1801, p. 1-66. [Also
available at
pp1801_Chap1_Tilling.pdf.]
2 Patrick, M.R., Orr, T., Fisher, G.B., Trusdell, F.A., and
Kauahikaua, J.P., 2017, Thermal mapping of a pāhoehoe
lava ow, Kīlauea Volcano: Journal of Volcanology and
Geothermal Research, v. 332, p. 71-87, doi: 10.1016/j.jvo-
lgeores.2016.12.007.
3 Turner, N.R., Perroy, R.L., and Hon, K., Lava flow hazard
prediction and monitoring with UAS: a case study from
the 2014-2015 Pāhoa lava flow crisis, Hawai‘i: Journal
of Applied Volcanology, v. 6, no. 17, 11 p., doi: 10.1186/
s13617-017-0068-3.
