Can statistics of turbulent tracer dispersion be inferred from camera observations of SO2 in the ultraviolet? A modelling study
- Author(s)
- Arve Kylling, Hamidreza Ardeshiri, Massimo Cassiani, Anna Solvejg Dinger, Soon-Young Park, Ignacio Pisso, Norbert Schmidbauer, Kerstin Stebel, Andreas Stohl
- Abstract
Atmospheric turbulence and in particular its effect on tracer dispersion may be measured by cameras sensitive to the absorption of ultraviolet (UV) sunlight by sulfur dioxide (SO2), a gas that can be considered a passive tracer over short transport distances. We present a method to simulate UV camera measurements of SO2 with a 3D Monte Carlo radiative transfer model which takes input from a large eddy simulation (LES) of a SO2 plume released from a point source. From the simulated images the apparent absorbance and various plume density statistics (centre-line position, meandering, absolute and relative dispersion, and skewness) were calculated. These were compared with corresponding quantities obtained directly from the LES. Mean differences of centre-line position, absolute and relative dispersions, and skewness between the simulated images and the LES were generally found to be smaller than or about the voxel resolution of the LES. Furthermore, sensitivity studies were made to quantify how changes in solar azimuth and zenith angles, aerosol loading (background and in plume), and surface albedo impact the UV camera image plume statistics. Changing the values of these parameters within realistic limits has negligible effects on the centre-line position, meandering, absolute and relative dispersions, and skewness of the SO2 plume. Thus, we demonstrate that UV camera images of SO2 plumes may be used to derive plume statistics of relevance for the study of atmospheric turbulent dispersion.
- Organisation(s)
- Department of Meteorology and Geophysics
- External organisation(s)
- Norwegian Institute for Air Research, Gexcon AS, PGS, Gwangju Institute of Science and Technology (GIST)
- Journal
- Atmospheric Measurement Techniques
- Volume
- 13
- Pages
- 3303–3318
- No. of pages
- 16
- ISSN
- 1867-1381
- DOI
- https://doi.org/10.5194/amt-13-3303-2020
- Publication date
- 06-2020
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 105206 Meteorology
- Keywords
- ASJC Scopus subject areas
- Atmospheric Science
- Portal url
- https://ucris.univie.ac.at/portal/en/publications/can-statistics-of-turbulent-tracer-dispersion-be-inferred-from-camera-observations-of-so2-in-the-ultraviolet-a-modelling-study(8e6a221e-16bb-4b90-ac14-36a496712400).html