Matthew Patrick E. Frank Younger William Tollett 20220328 raster digital data https://doi.org/10.5066/P9HQHDMH Following the 2018 collapses of the caldera floor at the summit of Kilauea Volcano (Anderson and others, 2019; Neal and others, 2019), the enlarged and deepened depression hosted a variety of volcanic activity between 2019 and 2022. These included an unprecedented water lake and two prolonged episodes of lava lake activity. This data release includes images from a stationary thermal camera poised on the western caldera rim, which provided a continuous record of the summit changes over this period. The thermal images provide an excellent observational record of the activity owing to the ability to see through thick volcanic fume, and the clarity with which they highlight active portions of the lava lake (Patrick and others, 2014). These thermal camera images cover three phases of activity at the summit of Kilauea. First, a water lake was present deep in Halema`uma`u crater from July 2019 to December 2020 (Nadeau and others, 2020). Second, a rising lava lake filled the bottom of Halema`uma`u from December 2020 to May 2021. Third, a second lava lake filled more of Halema`uma`u from September 2021 into early 2022 (through the end of this data release period in January 2022). References Anderson, K.R., Johanson, I.A., Patrick, M.R., Gu, M., Segall, P., Poland, M.P., Montgomery-Brown, E.K., and Miklius, A., 2019, Magma reservoir failure and the onset of caldera collapse at Kīlauea Volcano in 2018: Science, doi:10.1126/science.aaz1822 Nadeau, P.A., Diefenbach, A.K., Hurwitz, S., and Swanson, D.A., 2020, From lava to water: A new era at Kīlauea: Eos, 101, doi:10.1029/2020EO149557 Neal, C.A., Brantley, S.R., Antolik, L., Babb, J., Burgess, M., Calles, K., Cappos, M., Chang, J.C., Conway, S., Desmither, L., Dotray, P., Elias, T., Fukunaga, P., Fuke, S., Johanson, I.A., Kamibayashi, K., Kauahikaua, J., Lee, R.L., Pekalib, S., Miklius, A., Million, W., Moniz, C.J., Nadeau, P.A., Okubo, P., Parcheta, C., Patrick, M.R., Shiro, B,, Swanson, D.A., Tollett, W., Trusdell, F., Younger, E.F., Zoeller, M.H., Montgomery-Brown, E.K., Anderson, K.R., Poland, M.P., Ball, J., Bard, J., Coombs, M., Dietterich, H.R., Kern, C., Thelen, W.A., Cervelli, P.F., Orr, T., Houghton, B.F., Gansecki, C., Hazlett, R., Lundgren, P., Diefenbach, A.K., Lerner, A.H., Waite, G., Kelly, P., Clor, L., Werner, C., Mulliken, K., and Fisher, G., 2018, The 2018 rift eruption and summit collapse of Kilauea Volcano: Science, doi:10.1126/science.aav7046. Patrick, M., Orr, T., Antolik, L., Lee, L., and Kamibayashi, K., 2014, Continuous monitoring of Hawaiian volcanoes with thermal cameras: Journal of Applied Volcanology, v. 3, no. 1, doi:10.1186/2191-5040-3-1 Patrick, M.R., Swanson, D.A., Zoeller, M.H., Mulliken, K.M., Parcheta, C.E., Lynn, K.J., Downs, D.T., and Flinders, A.F., 2021, Water-level data for the crater lake at the summit of Kīlauea Volcano, Island of Hawaiʻi, 2019–2020: U.S. Geological Survey data release, https://doi.org/10.5066/P9262JDH. The thermal images were collected to monitor volcanic activity at the summit of Kilauea Volcano, Hawai`i. 20191101 20220201 ground condition Complete None planned -155.30926 -155.26016 19.43422 19.38856 ISO 19115 Topic Category farming USGS Thesaurus volcanic activity field inventory and monitoring volcanic rocks USGS Metadata Identifier USGS:61fc8cd2d34e622189cc1624 None USA HI Kilauea Volcano Halemaumau Common geographic areas Hawaii County Hawaii None. Please see 'Distribution Info' for details. Users are advised to read the dataset's metadata thoroughly to understand appropriate use and data limitations. Matthew Patrick U.S. Geological Survey, ALASKA REGION physical

1266 Kamehameha Avenue

Suite A8

Hilo HI 96720 US 808-967-8861 mpatrick@usgs.gov No formal attribute accuracy tests required. No formal logical accuracy tests required. Data set is considered complete for the information presented, as described in the abstract. Users are advised to read the rest of the metadata record carefully for additional details. No formal positional accuracy tests required. No formal positional accuracy tests required. Equipment and location The thermal camera is called the F1cam in the webcam naming scheme of the Hawaiian Volcano Observatory. The location of the camera was measured with a Trimble Geo7x GPS receiver, with an accuracy of 20 cm, to be 19.407494, -155.291750. This location is on the western caldera rim, with a commanding view of Halema`uma`u to the east. The ground elevation is 1141.16 m above sea level. The camera was measured as 1.0 m above ground level. The camera is a FLIR Systems A655sc thermal camera using a lens with a 45° horizontal field of view. The image dimensions are 640 x 480 pixels. The camera viewing geometry was estimated based on features in the image, with a viewing azimuth of 93° and a dip of 23.7°. The camera was not moved from the time of installation, though over time the view might have shifted slightly. The low temperature range setting (-40 to 120 °C) was used from the installation until December 21, 2020, when lava lake activity started. At that time, the camera was switched to the high range (100 to 650 °C), though occasionally the camera would forget this setting and briefly revert to the low range, resulting in temperature-saturated pixels over the lava lake. The camera is housed in a custom enclosure, made from a Pelican 1400 case, that has a Germanium window for the camera to see through (Patrick and others, 2014). The window is a 3-inch diameter size and 8 mm thick. The camera settings used to correct for atmospheric transmissivity and target emissivity were changed once during the study period. From the time of installation (October 2019) to June 16, 2020 (14:30 HST), the input distance was set to 1300 m, the ambient temperature was set to 20 °C, and the relative humidity was set to 50%. This produced an atmospheric transmissivity estimate of 0.75. No correction was applied for the transmissivity of the germanium window in the enclosure. The emissivity was set to 0.95 for basalt. On June 16, 2020, at 14:30 HST, the ambient temperature was set to 22.1 °C and the relative humidity was set to 64%. These values were based on an average of measurements from a weather station in the caldera. The distance was input as 1286 m. The “external optics transmission”, which accounts for transmissivity of the germanium window, was set to 0.86 based on blackbody tests in the lab. With the parameters of distance, ambient temperature, and relative humidity, the FLIR estimate of the atmospheric transmissivity was 0.67. There is a final parameter called “estimated transmission”, which we assumed accounted for the bulk transmissivity (external window and atmospheric transmission) and superseded the values estimated from the individual inputs like ambient temperature and humidity, and so we set this to 0.58 (0.86 x 0.67). However, in February 2022 we discovered that this “estimated transmission” only covers atmospheric transmissivity, and does not include the external window, so the effective bulk transmissivity between June 2020 and February 2022 had been incorrectly set to 0.50 (0.58 x 0.86), when it should have been higher (0.58). The emissivity was set to 0.99 for the water lake. 20220201 Image acquisition Image acquisition is controlled via Matlab using the GigeVision toolkit (Image Acquisition toolbox). From the time of installation (October 2019) to late October 2020, the image acquisition was controlled by a remote server that attempted to connect to the camera over the broader network, including a radio telemetry link. In practice, this resulted in many failed acquisitions, with only about 50% of the requested images being acquired. The resulting image acquisition rate was therefore highly irregular, spanning from three minutes to ten minutes or more. In late October 2020 we installed a single board computer (LattePanda) at the camera site to control the image acquisition. This local computer had a direct network connection to the camera, resulting in a more reliable image acquisition routine. The image acquisition success rate was 100%, resulting in a regular 2 minute acquisition rate after that time. There are occasional periods of missing data, lasting hours to days, due to power outages or other factors. 20220201 File format Each .zip file contains one month of data, named by the numerical month; in some cases the months are split into two .zip files, “a” and “b”, covering the first 15 days and the remainder of the month, respectively. The individual image files are organized into month, day and hour subfolders. Image file names contain the acquisition time in the format: YYYYMMDDHHmmSS. Each image is represented by two files. First, the raw data are contained in Matlab format (.mat), which is a double precision format. The .mat files contain two variables, an “img” variable containing the 640 x 480 matrix of image pixel values in degrees Kelvin, and a “ts” variable containing the acquisition time in Matlab datetime format. Acquisition time was returned by the “snapshot” function in the Matlab GigeVision toolbox; the acquisition computer time was synchronized over the network and should be accurate to within a second. Matlab (.mat) files can be opened with the open-source Python programming language using the mat4py or pymatreader packages. The second file is a .jpg format containing a JPEG image for easy viewing. 20220201 GS ScienceBase U.S. Geological Survey mailing address

Denver Federal Center, Building 810, Mail Stop 302

Denver CO 80225 United States 1-888-275-8747 sciencebase@usgs.gov Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data on any other system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. Digital Data https://doi.org/10.5066/P9HQHDMH None 20220328 Matthew Patrick U.S. Geological Survey, ALASKA REGION physical

1266 Kamehameha Avenue

Suite A8

Hilo HI 96720 US 808-967-8861 mpatrick@usgs.gov FGDC Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998