Three-dimensional cloud volume reconstruction from the Multi-angle Imaging SpectroRadiometer

Lee, Byungsuk

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https://hdl.handle.net/2142/99363 Copy

Description

Title

Three-dimensional cloud volume reconstruction from the Multi-angle Imaging SpectroRadiometer

Author(s)

Lee, Byungsuk

Issue Date

2017-12-12

Director of Research (if dissertation) or Advisor (if thesis)

Di Girolamo, Larry

Department of Study

Atmospheric Sciences

Discipline

Atmospheric Sciences

Degree Granting Institution

University of Illinois at Urbana-Champaign

Degree Name

M.S.

Degree Level

Thesis

Keyword(s)

• Cloud volume reconstruction
• Ray casting
• Remote sensing
• Multi-angle Imaging SpectroRadiometer (MISR)

Abstract

Clouds continue to contribute the largest uncertainty to estimates and interpretations of the Earth's energy budget, and their representation in climate models has been recognized for decades as a dominant source of uncertainty in climate change projections. It has been suggested that understanding the 3-D structure of cloud would lead to better understanding of the Earth's radiative and latent fluxes. Indeed, knowing cloud 3-D geometry could lead to: 1) improving our understanding of cloud microphysical properties and processes, and 2) improving our knowledge of the radiative effects of cloud on the Earth's energy budget. The Multi-angle Imaging SpectroRadiometer (MISR) is on board the Terra satellite, in its 17th year of operation as of 2017. MISR provides nine views of the same scene that allow scientists to visualize the 3-D structure of observed clouds to a certain extent. Taking advantage of such multi-angle characteristic, this project aims to reconstruct cloud volumes from MISR data. The reconstruction domain is defined such that it takes into account the curvature of the Earth’s ellipsoidal surface. The input satellite images used are the Radiometric Camera-by-camera Cloud Masks at 1.1 km resolution developed by the MISR science team, and custom cloud masks at 275 m resolution developed from MISR RGB images in this project. Due to the time difference between each camera view angle, wind correction is performed on the input cloud masks. For the reconstruction method, “ray casting” algorithms that fully account for the instrument's geometric properties are developed. The reconstruction results are presented for three hand-picked MISR cloud scenes. Strengths and limitations of the reconstruction method are explored, and the outlook for the use of the reconstruction results are discussed.

Graduation Semester

2017-12

Type of Resource

text

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http://hdl.handle.net/2142/99363

Copyright and License Information

Copyright 2017 Byungsuk Lee

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