Proceedings of the1st Academic Symposium on Integrating Knowledge UIN Makassar, 20-21 June 2014
DETECTION AED MONITORING OF UNDERGROUND FIRE SPREAD AT AL-NAJAF CITY IN IRAQ BY A REMOTE SENSING APPROACH Malik R. Abbas*1, Baharin Bin Ahmad1, Talib R. Abbas2 1 Department of Remote sensing, Faculty of Geoinformation and Real Estate, universiti Teknologi Malaysia, UTM, 81310 Johor Bahru, Johor, Malaysia 2 Environment and Water Directorate, Ministry of Science and Technology, Baghdad, Iraq * e-mail:
[email protected] ABSTRACT On 15th August 2010 a phenomenon of underground fire had occurred for the first time in the western province of Al Najaf in Iraq. Longitudinal cracks and small holes in the ground and emitted white smoke were observed. The cracks and smoke appeared clearly in an area of about 5000 m2. These observations were continued for the period of 15th August to 30th December 2010. MODIS data were used to detect if there is jump in thermal activity of this area during the observations period. MODIS data did not reveal a significant thermal activity jump in the study area through the period of 15th August 2010 to 20th October 2010. This may indicate that the area affected with underground fire is small relative to the spatial resolution of MODIS data which is 1 km. The area in which the cracks and smoke appeared (about 5000 m2) is relatively small when compared to the spatial resolution of MODIS. Therefore, this phenomenon probably did not reach the case of the threat of danger. KEYWORDS: Underground fire; Remote sensing; MODIS
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INTRODUCTION
The phenomenon of underground fire, sometimes with unknown reason and unknown boundary are an environmental and economic problem of international magnitude. Underground coal fires can be found in various countries around the world like the USA, Australia, China, Indonesia and Russia [1]. It is possible to apply remote sensing technology to detect underground fires and study their effects [2]. All hot bodies on the surface of the earth mostly emit radiation. In the zones of underground fire the land surface temperature become higher than the surroundings areas, so it is possible to apply remote sensing technology of thermal infrared to monitor the underground fire and the temperature anomalies [3]. The relation between underground fires and surface temperatures depends on several factors. Those factors are not just features of a surface, but are also affected by the conditions of the surrounding area. In the case of an underground fires, the surface temperature also depends on rock types and soil types; topography; local atmosphere; emissivity; crack or fissures on the surface; and depth of fire [4]. Electromagnetic spectrum (EMS) contains several regions in terms of wavelength. One of them is between 3 μm to 14 μm, known as thermal infrared region. The atmospheric windows are in the range of 3 μm to 5 μm and 8 μm to 14 μm., These ranges are only used in thermal remote sensing, because these parts of the EMS spectrum are not affected as much by atmospheric interaction [5]. Thermal and optical images along with field-based measurements are used for determination of location, size, and depth, burning intensity, propagation direction, and temperature as well as mapping various geo-environmental features like coal fires, oil-well fires, forest fires, and volcanic eruptions [2]. Detection of high temperature anomalous areas in by various thermal scanners are operated in different countries with several platforms, like Landsat7 ETM+ band 6 (presently non-functional because of scanner failure) & Landsat 5 band 6 [6] and ASTER band10 to band 14. In addition, for a large area, AVHRR instrument (on the NOAA series of polar-orbiting satellites) is recording the earth’s surface thermally with a spatial 188
resolution of 1.1 km and MODIS (Moderate Resolution Imaging Spectroradiometer) is acquiring data in the thermal infrared region (spatial resolution 1 km), which are being used in many applications in meteorology and earth observation [6]. There are three steps in the use of remote sensing technique in order to detect an understand fires: 1The first step is to get the satellite thermal image of the area to be studied and processed digitally to obtain the thermal map of the surface area, for the purpose of detection of thermal anomalies. 2Gather information about temperatures of the holes from which the graduated fire, geological case of the region and types of vegetation found in the region, this is done through field survey [7]. 3Use the geological field and other field knowledge to eliminate anomalies, other than underground fires to creating a final temperature map that is calibrated with the temperatures that were collected through field survey [8]. After the satellite data are available, like thermal scanner data, it is possible to study the phenomena's of underground fires. Studies were carried out of this regard in United States, Australia, India and China. Cracknell and Mansoor (1992) used data of Landsat-5 TM and NOAA-9 AVHRR and found that nighttime NOAA data was quite useful to isolate the hot spots from the background [9]. Another study carried out by Reddy et al. (1993), who used scanner that detect the short-wave infrared (SWIR) region of the EMR on board of Landsat TM band 4, 5 and 7. They found that the warm area in the image corresponded well with the field measurements [10]. In the same area, Saraf et al. (1995) used Landsat TM band 6 and 7 and found that comparatively high hotspots should correspond with surface fires, while the less warm areas should correspond with subsurface fires [11]. In China Wan and Zhang (1996), and Zhang et al. carried out a detailed study in the same area. They used daytime Landsat TM band 6 data to estimate the relative amount of solar illumination during the overpass time, which was used to correct for the effect of terrain. Since the spatial resolution of Landsat 5 thermal band is poor (120m), he failed to detect small fires [12]. This research is an attempt to get meaningful indication about the size of the underground fire area that occurred in the area AL-Ruhban in AL Najaf city - Iraq in September 2010. 2
STATEMENT OF THE PROBLEM
On 15th August 2010 a phenomenon had occurred for the first time in the western province of Al Najaf in Iraq. Figures 1 a), b), c) and d) shows the observed longitudinal cracks and small holes in the ground which emitted white smoke. The region in which this phenomenon had occurred is an oasis in a desert area. Oasis area is about 2.7 km in length and 1.6 km widths. The cracks and smoke appeared clearly in an area of about 5000 m2. These observations were carried out for the period of 15th August 2010 to 30th October 2010.
Figure 1 Observed longitudinal cracks and small holes in the ground and emitted white smoke
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Study Area
The study area is located in western province of Najaf – Iraq, about 79 km (direct distance) from Najaf city center. It lies between latitudes 31° 51' – 31° 52' northing and longitudes 43° 33' – 43° 34' easting (see Figure 2). It covers an area of about 4.32 km2. Geological Site: It lies some distance (18 km) from the Abu Jir Fault zone. This Fault lies between latitudes 31o 00' – 34o 00' northing and longitudes 42º 00' – 46o 00' easting. It extends from Al-Anbar city passing through the villages of Kubaisa, Heet, Al-Awasit and Abu-Jir village, Karbala city (Shithatha), Al-Najaf city (Bahr Al-Najaf) and Al-Diwania city (Al-Samawa). It lies on the border line between the stable and unstable region [13]. 3.1
Climate of the Study Area
The climate of the study area is considered to be of desert condition, where it is characterized by a dry summer and cold with scarce rain in winter. The climatologically data were obtained from the Iraqi meteorological organization for four climate stations i.e., Anbar, Karbala, Najaf and Samawa stations for the time period of 1971-2007 [14]. The mean monthly data, averaged over the period 1971-2007 for each meteorological element for the above time period is given in Table 1.Also Table 2 given the means monthly data for the year 2010 obtained from Najaf meteorological station.
Figure 2 Location of the study area
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