Spatial Analysis of the CO Emission from Nineveh Governorate Using Remote Sensing Techniques and GIS

Carbon Monoxide (CO) has a significant indirect effect on greenhouse gasses due to its ozone and carbon dioxide precursor, and its mechanism of degradation involving the hydroxyl radical (OH) which control the oxidizing ability of the tropospheric. To understand the effect of human activities on atmospheric composition, accurate estimates of the sources of atmospheric carbon monoxide (CO) are necessary. MOPITT (Measurements of Pollution in the Troposphere) is a NASA Terra satellite instrument designed to allow both Thermal-Infra-Red (TIR) and Near-Infra-Red (NIR) observations to be used to collect vertical CO profiles in the Troposphere via the concept of correlation spectroscopy. The objective of the current study is to analyze and map the monthly, seasonal and annual trend of CO concentration for year 2016 in Nineveh governorate using the retrieved CO Surface Mixing Ratio Day mode of level 3, version 7 dataset. The dataset was downloaded from the National Aeronautics and Space Administration (NASA) operated GIOVANNI portal. The results of dataset analysis in GIS software showed many sources of carbon monoxide in Nineveh Governorate, which change with months and seasons of the year. Generally, the observed CO concentration levels in the southern and western of the governorate were more than in the northern and eastern parts. The annually average CO ranges from (115.374 ppbv) to (132.452 ppbv). Also, CO emissions and concentrations were higher in winter (128.638-157.567 ppbv) than summer season (97.144-106.515 ppbv). Keyword: MOPITT, GIS, CO, Nineveh, Terra تساب ىهنين ةظفاحم نم نهبراكلا ديدكوا لوا تاثاعبنلأ يناكملا ليلحتلا لامع يئانلا سدحتلا تاناقت ةيفا رغجلا تامهلعملا مظنو يلع نيدح حابص * 1 نيدلا مجن دمحأ محمد ، 2 1 قا رعلا ,ىهظين ةعفاحم ,لصهطلا ةعماج ,يئاظلا سسحتلا زكرم 2 قا رعلا , ةئيبلاو ةحصلا ةرا زو ةصلاخلا ( نهبراكلا ديسكوا لوا زاغ بعمي CO يف رشابم ريغو اطهم ا رود ) لا نزاهت ىمع هريثأت ببسب ةئيفدلا تا زاغ ( لاكيدا ر ليسكورديهلا OH ( نوزولااو ) O3 ةسا رد بمطتيو .يمفسلا يهجلا فلاغلا يف ةيئايطيكلا تايمطعلاو ) ديدحت ، يهجلا فلاغلا يف نهبراكلا ديسكوا لوا زاغ ةبسن ىمع ةيرشبلا ةطشنلاا ريثأت لا ةيسيئرلا رداصط ISSN: 0067-2904 Ali and Najemaden Iraqi Journal of Science, 2021, Vol. 62, No. 11(Special Issue), pp: 4503-4517 4054 .زاغلا اذهل رتلا يف ثهمتلا تاسايق سسحتم ربتعي و ( ريفسهب MOPITT ) دحأ دعب نع راعشتسلاا تامهعظم لهطحطلا ( ا ريت يعاظطصلاا رطقلا ىمع ة TERRA ةيهجلا ةحلاطمل ةيظطهلا ةرادلإل عباتلا ) ( ءاضفلاو NASA ،) ةمزح للاخ نم ريفسهبورتلا ةقبط يف نهبراكلا ديسكوا لوا زاغ زيكا رت ليجستو دصرل سسحتطلا اذه مطص ( ةيرا رحلا ءا رطحلا تحت ةعشلاا TIR ةبيرقلا ءا رطحلا تحت ةعشلااو ) ( NIR للاخ نم ) .يفيطلا ليمحتلا مههفم ديسكأ يناث زيكرتل يهظسلاو يطسهطلاو يرهشلا هاجتلاا طئا رخ ليمحتو ليثطت هه ةيلاحلا ةسا ردلا نم فدهلا (ماعل ريفسهبورتلا ةقبط يف نهبركلا 2016 تساب ىهظين ةعفاحم يف ) لاطع زاغمل ةعجرتسطلا تافمطلا جذاطن (ىهتسطلا يف يراهظلا عضهلا نطض 3 (رادصلإاو ) 7 ةباهب نم تانايبلا ليطحت مت .) GIOVANNI) يتلا ) ( اهريدت NASA لوأ رداصم نم ديدعلا ةيفا رغجلا تامهمعطلا معن تايجمرب يف تانايبلا ليمحت جئاتن ترهظأ .) ديسكأ يناث زيكرت تايهتسم تناك .ةظسلا لهصفو رههش عم ريغتت يتلاو ىهظين ةعفاحم يف نهبركلا ديسكأ بركلا يهظسلا طسهتطلا حوا رت .ةيقرشلاو ةيلاطشلا ءا زجلأا يف اهظم ىمعأ ةعفاحطلا برغو بهظج يف ةظهحمطلا نه نم نهبركلا ديسكوأ لوا زيكرتل (115.374 ppbv) ىلإ (132.452 ppbv). تاثاعبنا تناك ، اضًيأ . ءاتشلا يف ىمعأ نهبركلا ديسكأ يناث تا زيكرتو (128.638-157.567 ppbv) ب ةنراقم فيصلا مسهط (97.144-106.515 ppbv) .

Information System (GIS) software for the cartographic representation of the output results. While some researches relied mainly on analyzing CO distribution maps that can be accessed and activated directly from CO MOPITT data sites [ 9,10].

2.
Region of Interest Nineveh governorate is located in northwestern Iraq between the latitudes (34 °: 56' and 37 °: 03') north and longitudes (41 °: 25' and 44 °: 25') east as shown in Figure 1. Its estimated total land area is 37,323 km 2 . The surface of the Nineveh Governorate is described by its varying topographical characteristics from one region to another, its surrounding hills and high mountain chains affect wind direction, lowlands and paths [11]. The climate of studied region is classified as semi-arid, subtropical, Mediterranean climate, with a hot, dry summer and cold winter climate. In winter and spring, most rain occurs (October to May). No rainfall during summer (June-September period) [12]. MOPITT Background Since 1999, the Canadian MOPITT instrument has continuously scanned the Earth's atmosphere for long-term measurements of CO concentration level. It was one of five instruments launched on 18-December-1999 on the Terra satellite, by the (NASA) [13]. The MOPITT instrument used correlation spectroscopy concept to measure the concentrations of carbon monoxide (CO) at three troposphere levels using thermal radiation at 4.7 µm, total column level of CO, and methane CH 4 by reflected sunlight at around 2.3 µm. Correlation spectroscopy uses a gas-containing sample cell to be measured in a simple radiometer path and modulates the amount of gas in the cell. The resulting signal can be analyzed to visualize enhanced radiance sensitivity at optical frequencies near the target gas spectral lines. To reach its goals, the MOPITT system uses two gas modulation cells: Pressure Modulation Cell (PMC) and Length Modulation Cell (LMC) as shown in Figure 2. Here, the signal passes through a cell that contains the target gas (CH 4 or CO) varying according to cell pressure or length, that results a variation of cell opacity along the target gas lines, while the cell opacity stays constant at other frequencies [14].  * no longer available For each CO retrieval process, the MOPITT retrieval algorithm needs a dataset of temperature, water vapor profiles, and a priori surface temperature values which are derived from meteorological stations [8].

Data Access and Processing
Retrieved CO Surface Mixing Ratio Day mode of level 3 version 7 dataset, was taken from NASA-operated GIOVANNI portal [19]. The dataset was express in unit of Part Per Billion Volume (ppbv) and covered all Nineveh governorate area as a grid of 12-points with a uniform grid interval of 1-degree latitudes-longitudes as shown in Figure 3 below. The retrieved CO was downloaded for period from 1 st -January to 31 st -December 2016. Generally, the MOPITT data were archived and delivered using Hierarchical Data Format (HDF) which is the common data format for all NASA Earth Observing System (EOS) datasets. The HDF-EOS extension is a swath structure defined along with the Application Program Interfaces (APIs). The API offers functionality for creating, accessing and manipulating grid, point and swath configurations [20]. The HDF-EOS products can be processed, analyzed and visualized into Panoply software [21]. Panoply is an advanced and complex Java application designed to enable users to easily plot raster images of geo-gridded datasets of HDF-EOS extension. In order to reach the stage of mapping the average distribution of carbon monoxide concentrations, the following steps were followed in the study: 1-CO MOPITT datasets of the study area were accessed and downloaded from the Giovanni website for the 12 months of year 2016. 2-The CO downloaded datasets were opened using Panoply visualization software (version 4.10.3). Grids/MOPITT files for each month was selected. The variable's full name of the files is: HDFEOS/GRIDS/MOP03/Data_Fields/RetrievedCOSurfaceMixingRatioDay 3-From the Panoply windows, selecting a month variable enables the plotting function in the data browser, then plot window will display a map. The data array used to create the map is tucked away behind the map tab in the plot window. The values for individual grid cells for the displayed map will be listed by latitude/longitude in separate column. The grid cells values of the study area for each month will be selected according to the geographical coordinates and copied to be pasted in Excel files. 4-Finally, the Excel files for the 12 months will be add to ArcGIS10.6, converted to shapefiles and Spatial Analyst/ Inverse Distance Weight (IDW) interpolation function will be done to creates the CO spatial concentration mapping over the Nineveh governorate. The IDW gave best representation for the MOPITT CO dataset adopted in the present study. IDW interpolation is good when the points in a region are distributed evenly and systematically [22].

Results and Discussion
This study aims to evaluate the trend of CO concentration over Nineveh governorate using MOPITT dataset of the year 2016 (1 st January -31 st December). Figure 4 and Figure 5 shows the monthly average of the CO concentration at the surface level. The CO concentration values show spatial variation according to months on most parts of the study area, especially in the western, southern parts and the center of the governorate (Singar, Baaj, Hadher, Talafar, and Mosul). It shows maximum levels in January (167 ppbv     There are several reasons for monthly, seasonal, or annual spatial changes in CO concentrations over Nineveh governorate. In Mosul city, it is resulted from the large number of human population (estimated 1,588,427 in 2011), many human activities, large number of cars as well as large number of diesel generators that are used to generate electricity for homes [24]. In the south of Mosul, specifically the Qayyarah region, which is characterized by the presence of many oil fields, the terrorist organization ISIS burned many of these oil fields, that led to emission of large quantities of pollutants plume to reach the atmosphere including CO .This pollutants plume was extended to the neighboring districts. The fires in the oil fields continued from mid-June 2016 to the last of March 2017 [25]. Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA Terra satellite recorded daily fire detection data of these fires for (1-May-2016 to 28-October-2016), Figure 9.  During the period of the occupation of Nineveh governorate by the terrorist organization ISIS, many old technology of small refiners called (Harraqat) were installed to produce oil products (specially different types of car fuel), all these Harraqat work without any air pollution control measurements leading to discharge heavy pollutants including CO to atmosphere [26]. Most of these Harraqat were concentrated in the south and west of the governorate, Figure 10. The same technology was used along the Syrian -Iraqi borders, which also caused an increase in CO concentrations in west parts of the study area with very small contribution to CO concentrations to the central, north and east parts.  Figure 5 above, is Mishraq Sulfur Factory fire, which continued from 21 -27 October, 2016. It also emitted a large quantity of SO 2 and other pollutants plume including CO gas [27]. Figure 11 shows a satellite image acquired by NASA's Aura and Soumi satellites carry the Ozone Monitoring Instrument (OMI) and Global Ozone Monitoring Experiment-2 (GOME-2) described the spreading of the pollutants plume from 22 to 27 October, 2016 [ 28]. From the study results, it was noticed that the highest monthly average CO concentration level appeared in January (167.008 ppbv), while the highest level in the seasons appeared in winter (157.567 ppbv) and the highest annually level was (132.452 ppbv). By comparing these values with the Iraqi national ambient air standards and European air quality standards related to the air quality, including CO (9000 ppbv) measures over an eight hour period, it can be seen that the level of pollution with this gas in all districts of Nineveh governorate is very, very far from dangerous level [29,30].

Conclusions
The study focused on a period during which the Nineveh governorate was under the control of the terrorist organization ISIS, 1 st January -31 st December, 2016, when there were many variables that affected the levels of CO emission to the troposphere. From the results, it can conclude the following: 1-The retrieved MOPITT CO dataset detected by infrared thermal band at the lower troposphere are able to provide valuable information on CO surface emissions. 2-The observed seasonal and annually CO concentration levels in the southern and western districts of the governorate and south of Mosul is much higher than the northern and eastern districts, the annually average CO concentration ranges from (115.374 ppbv) in the north and east of the governorate, to (132.452 ppbv) in the south and west. Also, CO emissions and concentrations were higher in winter (128.638-157.567 ppbv) than in summer season (97.144-106.515 ppbv). 3-. Qayyarah Oil field and Mishraq sulfur factory fires as well as the man-made of small refiners (Harraqat) increased significantly CO concentration levels in west, south and middle parts of the study area. 4-All CO concentration levels were within national standards limit of ambient air quality as well as European air quality standards.