Determination of Haze from Satellite Remotely Sensed Data: Some Preliminary Results
Asmala Ahmad and Mazlan Hashim
Faculty of Engineering and Geoinformation Science
Universiti Teknologi Malaysia
Locked Bag 791, 80990 Johor Bahur
Phone : 07-5502940 Fax : 07-5566163
E-mail : mazland@fksg.utm.my
Abstract
This paper reports some preliminary results of a study conducted at Centre for Remote Sensing UTM in attempt to quantify haze (total suspended particulates) from NOAA AVHRR data. The relationship between measured total suspended particulates (TSP) and satellite recorded digital number (DN) were analysed. TSP measurements were carried out by Malaysian Meteorological Services at eight air pollution stations located in Peninsular Malaysia. Initial results of this relationship were shown as regression plots namely, linear, logarithmic, polynomial, power and exponential.
Introduction
Haze can be defined as a partially opaque condition of the atmosphere caused by very tiny suspended solid or liquid particulars in the air (Morris, 1975). Haze, related to atmospheric aerosol released from an open burning or forest fire contains large amount of trace gases (e.g., CO2, CO, CH4, Nox) and particulates (e.g., organic matter, graphitic carbon). Haze is hazardous to health, especially associated with lung and eye diseases. Long term haze occurrence will increase the atmospheric greenhouse effects besides affecting the trospheric chemistry. Thus, haze occurrence should be identified so that necessary measures could be taken to curb such occurrence. Conventionally, haze can be determined from ground measurements instruments such as air sampler, sun photometer, and optical particle counter, however these instruments could not detect an early sign of haze and is impractical if measurement are to be made over relatively large areas or for continuous monitoring.
The haze episode occurred during mid-August to October 1994 is considered one of the worst since 1980 (four similar haze episodes had occurred in April 1983, August 1990, June 1991 and October 1991). It was due to the injection of suspended ash particulates from large scale forest fie in Sumatra and Kalimantan. In addition, the occurrence of shallow localized haze in Klang Valley since the past two decades during the South West Monsoon Season (months of July to September) acted as the minor contributor that made the condition worse. Such phenomenon (which was not a new experience for Malaysia) has created moiré awareness among the people concerning the haze problem and more commitment are put to curb haze occurrences effectively.
This paper reports some preliminary results in attempt to quantify haze from NOAA AVHRR data. Initial relationship between TSP and satellite DN were shown at eight air pollution stations namely Bayan Lepas, Petaling Jaya, Perai, Melaka, Kuala Terengganu, Mersing, Endau, Kuantan and Batu Embun.
