气候变化领域集成服务门户(CCPortal): Atmospheric and emissivity corrections for ground-based thermography using 3D radiative transfer modelling

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DOI	10.1016/j.rse.2019.111524
	Atmospheric and emissivity corrections for ground-based thermography using 3D radiative transfer modelling
	Morrison W.; Yin T.; Lauret N.; Guilleux J.; Kotthaus S.; Gastellu-Etchegorry J.-P.; Norford L.; Grimmond S.
发表日期	2020
ISSN	00344257
卷号	237
英文摘要	Methods to retrieve urban surface temperature (Ts) from remote sensing observations with sub-building scale resolution are developed using the Discrete Anisotropic Radiative Transfer (DART, Gastellu-Etchegorry et al., 2012) model. Corrections account for the emission and absorption of radiation by air between the surface and instrument (atmospheric correction), and for the reflected longwave infrared (LWIR) radiation from non-black-body surfaces (“emissivity” correction) within a single modelling framework. The atmospheric correction a) can use horizontally and vertically variable distributions of atmosphere properties at high resolution (<5 m); b) is applied here with vertically extrapolated weather observations and MODTRAN atmosphere profiles; and c) is a solution to ray tracing and cross section (e.g. absorption) conflicts (e.g. cross section needs the path length but it is typically unavailable during ray tracing). The emissivity correction resolves the reflection of LWIR radiation as a series of scattering events at high spatial (<1 m) and angular (ΔΩ ≈ 0.02 sr) resolution using a heterogeneous distribution of radiation leaving the urban surfaces. The method is applied to a novel network of seven ground-based cameras measuring LWIR radiation across a dense urban area (extent: 420 m × 420 m) where a detailed 3-dimensional representation of the surface and vegetation geometry is used. Our unique observation set allows the method to be tested over a range of realistic conditions as there are variations in: path lengths, view angles, brightness temperatures, atmospheric conditions and observed surface geometry. For pixels with 250 (±10) m path length the median (5th and 95th percentile) atmospheric correction magnitude is up to 4.5 (3.1 and 8.1) K at 10:10 on a mainly clear-sky day. The detailed surface geometry resolves camera pixel path lengths accurately, even with complex features such as sloped roofs. The atmospheric correction method evaluation, with simultaneous “near” (~15 m) and “far” (~155 m) observations, has a mean absolute error of 0.39 K. Using broadband approximations, the emissivity correction has clear diurnal variability, particularly when a cool and shaded surface (e.g. north facing) is irradiated by warmer (up to 17.0 K) surfaces (e.g. south facing). Varying the material emissivity with bulk values common for dark building materials (ε = 0.89 → 0.97) alters the corrected roof (south facing) surface temperatures by ~3 (1.5) K, and the corrected cooler north facing surfaces by less than 0.1 K. Corrected observations, assuming a homogeneous radiation distribution from surfaces (analogous to a sky view factor correction), differ from a heterogeneous distribution by up to 0.25 K. Our proposed correction provides more accurate Ts observations with improved uncertainty estimates. Potential applications include ground-truthing airborne or space-borne surface temperatures and evaluation of urban energy balance models. © 2019 Elsevier Inc.
英文关键词	3D radiative transfer; Atmospheric correction; DART; Emissivity correction; Ground-based thermography; Urban meteorology
语种	英语
scopus关键词	Angular distribution; Cameras; Electromagnetic wave emission; Geometry; Infrared radiation; Pixels; Radiative transfer; Ray tracing; Remote sensing; Roofs; Surface properties; Thermography (imaging); Uncertainty analysis; 3-dimensional representation; Atmospheric corrections; DART; Ground based; Heterogeneous distributions; Radiative transfer modelling; Urban meteorology; Urban surface temperature; Atmospheric temperature; atmospheric correction; energy balance; ground-based measurement; meteorology; radiative transfer; remote sensing; spatial resolution; surface temperature; three-dimensional modeling; urban area
来源期刊	Remote Sensing of Environment
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/179510
作者单位	Department of Meteorology, University of Reading, Earley Gate, ReadingRG6 6BB, United Kingdom; Earth System Science Interdisciplinary Center, University of Maryland, United States; CESBIO, Toulouse University (CNRS, CNES, IRD, UPS), Toulouse, France; Institut Pierre Simon Laplace (IPSL), Ecole Polytechnique, France; Department of Architecture, Massachusetts Institute of Technology, Cambridge, MA, United States
推荐引用方式 GB/T 7714	Morrison W.,Yin T.,Lauret N.,et al. Atmospheric and emissivity corrections for ground-based thermography using 3D radiative transfer modelling[J],2020,237.
APA	Morrison W..,Yin T..,Lauret N..,Guilleux J..,Kotthaus S..,...&Grimmond S..(2020).Atmospheric and emissivity corrections for ground-based thermography using 3D radiative transfer modelling.Remote Sensing of Environment,237.
MLA	Morrison W.,et al."Atmospheric and emissivity corrections for ground-based thermography using 3D radiative transfer modelling".Remote Sensing of Environment 237(2020).