Volcanic plume heights from the summit of Kilauea Volcano, Hawai'i

This data release provides volcanic plume heights from the summit of Kilauea Volcano for 2008-2015, and during the eruptive events of 2018. For 2018, a Secacam Wild Vision Full HD camera with a 7mm focal length was located at 1717 m elevation approximately 15 m south of the Mauna Loa Strip Road within Hawai'i Volcanoes National Park, 19.475843degreesN, 155.363560degreesW (WGS84). The camera was pointed southeast to capture images of the Kilauea caldera every two minutes. These images were used to calculate maximum plume heights within the full frame of the camera. For each two-minute image, the maximum plume heights above the Halema'uma'u crater rim, and in the overall image, were calculated using the horizontal distance to the plume feature, the inclination angle, camera focal length, pixel size, and basic trigonometry. For 3,518 images the plume height above Halema'uma'u crater represents the maximum height in the image, and a '0' is indicated for the overall image (camera frame) plume height. For 4,325 images, no visible plume was discernable in the image directly above Halema'uma'u (as a result of fog, clouds, plume moving downwind, or other factors), and the maximum plume height in the entire camera frame is reported, with a '0' indicated for the Halema'uma'u plume height. Included in the release are all 83,320 images from 9 April, 2018 to 16 August, 2018. These images include both day and night, whether or not a plume is visible. Plume height data from 31 March, 2008 to 23 April, 2015 were recorded by an observer using a handheld inclinometer while standing close to the corner of the low rock wall at the Jaggar overlook at 19.251065degreesN, 155.171629degreesW (WGS84). Date, time, approximate location of the highest plume feature, and inclination angle were recorded. The horizontal distance to the highest plume feature, the inclination angle, and basic trigonometry were used to calculate the maximum plume height above the elevation of the vent within Halema'uma'u.

本数据集发布内容涵盖2008年至2015年，以及2018年火山喷发事件期间基拉韦厄火山（Kilauea Volcano）山顶的火山柱高度数据。针对2018年的观测数据，研究人员在夏威夷火山国家公园内、莫纳罗亚步道（Mauna Loa Strip Road）以南约15米、海拔1717米处架设了一台Secacam Wild Vision全高清（Full HD）相机，该相机焦距为7mm，拍摄坐标为北纬19.475843°、西经155.363560°（WGS84坐标系）。相机朝向东南方向，每2分钟拍摄一张基拉韦厄破火山口的图像。研究人员借助火山柱特征与相机的水平距离、倾角、相机焦距、像素尺寸及基础三角学原理，对每张2分钟间隔图像的全幅视场内的最大火山柱高度进行计算。其中，针对3518张图像，哈莱马乌马火山口（Halema'uma'u crater）边缘上方的火山柱高度为该图像中的最大高度，此时整张相机视场的火山柱高度记为0；针对4325张图像，哈莱马乌马火山口正上方未观测到可见火山柱（可能由雾霭、云层、火山柱顺风飘散或其他因素导致），此时统计整张相机视场内的最大火山柱高度，并将哈莱马乌马火山口边缘上方的火山柱高度记为0。本次发布涵盖2018年4月9日至8月16日的全部83320张图像，包含昼夜时段的拍摄结果，无论图像中是否存在可见火山柱。2008年3月31日至2015年4月23日的火山柱高度数据由观测人员使用手持倾角仪记录获得，观测点位位于贾格尔观测点（Jaggar overlook）的低矮石墙角落附近，坐标为北纬19.251065°、西经155.171629°（WGS84坐标系）。观测过程中记录了日期、时间、最高火山柱特征的近似位置及倾角，并基于最高火山柱特征与观测点的水平距离、倾角及基础三角学原理，计算得出哈莱马乌马火山口内喷口海拔以上的最大火山柱高度。