Estimating Geo‐Referenced Cloud‐Base Height With Whole‐Sky Imagers. Issue 8 (11th August 2021)

• Record Type: Journal Article
• Authors: Lyu, Baolei; Chen, Yang; Guan, Yuqiu; Gao, Tianlei; Liu, Jun
• Is Part Of: Earth and space science. Volume 8:Issue 8(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-08-11
• Subjects: cloud‐base height -- geo‐reference -- whole‐sky imager; Space sciences -- Periodicals; Geophysics -- Periodicals; 500.5
• DOI: 10.1029/2019EA000944
• Languages: English
• ISSNs: 2333-5084

Abstract

Abstract: Accurate and frequent cloud‐base height calculation is beneficial to solar farming and agricultural activities and also indicative for future meteorology conditions. This study used paired whole‐sky imagers to estimate cloud‐base height with high quality. The study obtained quality assured cloud base feature points with a robust Shi‐Tomasi‐Scale Invariant Feature Transform algorithm before employing double‐eye locating approach, which is fast and easy to implement operationally. The estimated cloud‐base heights have high spatial coverages. Evaluated against ceilometer observations, estimated cloud‐base heights have a high accuracy level, with R 2 = 0.92 and RMSE = 424 m. The method is generally unbiased with NME = 9.2%. The high‐quality cloud‐base features in this study are quantitatively geo‐referenced, which would benefit a lot to meteorological studies such as fusion with satellite observations, evaluation for model simulations and upper‐level wind specifications. Plain Language Summary: The cloud‐base height is an important indicator for meteorological conditions especially in the upper‐level atmosphere, which is generally hard and expensive to obtain. Thanks to the development of computer vision, we could be able to obtain three‐dimensional information from two‐dimensional images. The whole sky cameras are often used to capture images of cloud, from which we calculated cloud‐base height with high accuracy. Besides, these cloud heights data are geo‐referenced. This will enable data fusion with instrument observations, modeling simulations and satellite remote sensing, greatly expanding their appliance in atmospheric studies. Key Points: Cloud‐base heights are operationally calculated from paired whole‐sky imagers Cloud‐base heights are geo‐referenced with explicit four‐dimension spatiotemporal coordinates