Please use this identifier to cite or link to this item:
Title: Fine resolution air quality monitoring from a small satellite : CHRIS/PROBA
Authors: Nichol, JE 
Wong, MS 
Chan YY 
Keywords: Aerosol
Surface reflectance
Issue Date: 2008
Publisher: Molecular Diversity Preservation International (MDPI)
Source: Sensors (Switzerland), 2008, v. 8, no. 12, p. 7581-7595 How to cite?
Journal: Sensors (Switzerland) 
Abstract: Current remote sensing techniques fail to address the task of air quality monitoring over complex regions where multiple pollution sources produce high spatial variability. This is due to a lack of suitable satellite-sensor combinations and appropriate aerosol optical thickness (AOT) retrieval algorithms. The new generation of small satellites, with their lower costs and greater flexibility has the potential to address this problem, with customised platform-sensor combinations dedicated to monitoring single complex regions or mega-cities. This paper demonstrates the ability of the European Space Agency's small satellite sensor CHRIS/PROBA to provide reliable AOT estimates at a spatially detailed level over Hong Kong, using a modified version of the dense dark vegetation (DDV) algorithm devised for MODIS. Since CHRIS has no middle-IR band such as the MODIS 2, 100 nm band which is transparent to fine aerosols, the longest waveband of CHRIS, the 1, 019 nm band was used to approximate surface reflectance, by the subtraction of an offset derived from synchronous field reflectance spectra. Aerosol reflectance in the blue and red bands was then obtained from the strong empirical relationship observed between the CHRIS 1,019 nm, and the blue and red bands respectively. AOT retrievals for three different dates were shown to be reliable, when compared with AERONET and Microtops II sunphotometers, and a Lidar, as well as air quality data at ground stations. The AOT images exhibited considerable spatial variability over the 11 × 11km image area and were able to indicate both local and long distance sources.
ISSN: 1424-8220
DOI: 10.3390/s8127581
Rights: © 2008 by the authors; licensee Molecular Diversity Preservation International, Basel, Switzerland. This article is an open-access article distributed under the terms and conditions of the Creative Commons Attribution license (
The following publication Nichol, J. E., Wong, M. S., & Chan, Y. Y. (2008). Fine resolution air quality monitoring from a small satellite: CHRIS/PROBA. Sensors, 8(12), 7581-7595 is available at
Appears in Collections:Journal/Magazine Article

Files in This Item:
File Description SizeFormat 
Nichol_Fine_Resolution_Air.pdf784.92 kBAdobe PDFView/Open
View full-text via PolyU eLinks SFX Query
Show full item record
PIRA download icon_1.1View/Download Contents


Citations as of Feb 9, 2019


Last Week
Last month
Citations as of Feb 20, 2019

Page view(s)

Citations as of Feb 19, 2019


Citations as of Feb 19, 2019

Google ScholarTM



Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.