Change Detection between Landsat 8 images and Sentinel-2 images

Abstract

The technology of change detection is a technique by which changes are verified in a certain time period. Remote sensing images are used to detect changes in agriculture land for the selected study area located south of Baghdad governorate in Agricultural Division of AL-Rasheed district because this method is very effective for assessing change compared to other traditional scanning techniques. In this research two remotely sensed images for the study area were taken by Landsat 8 and Sentinel-2, the difference between them is one month to monitor the change in the winter crops, especially the wheat crop, where the agriculture began for the wheat crop there in the Agricultural Division of AL-Rasheed district at 15/11/2018. The first preprocessing procedure was the extraction of the NDVI (Normalized Difference Vegetation Index) values for the two scenes of Landsat 8 and the two scenes of Sentinel-2B and then using the change detection between them to compare the changes in agriculture land. Also, change detection was implemented between NIR bands because they are most severely affected by biomass or the amount of available chlorophyll-containing in plant structures. The results of the change detection for Sentinel-2B were more accurate than for the Landsat 8 as demonstrated by field visits for the study area, where the changes in the distribution of vegetal cover (wheat and other winter crops) were clear and accurate in the image of Sentinel-2B, as opposed to Landsat's 8 image, where the variation in vegetation cover was not accurate, especially for the change detection between NIR bands.

Irregular urban Expansion and Its Effects on Air Temperature over Baghdad City using Remote Sensing Technique

“…On a hot sunny summer day, sunlight can heat dry exposed surfaces in urban areas, such as surfaces and paving, to temperatures ranging from 27-50 °C warmer than air, while shaded or wet surfaces, which often are in the surrounding rural areas, remain close to the air temperatures [12]. In Baghdad city, there is an increase in the urban area to about 15% in recent years, on account of open and agricultural land [13,14].…”

“…This is achieved by two methods, one of which is based on the lower and higher spectral radiation values (radiance minimum and maximum) that is extracted from the Metadata file type and the sensor of the satellite. It is calculated according to the spectral radiation equation of the satellite, that is given as [19]: The second method is to convert radiation values to temperatures, as in the following equation [20]: ----------------------( -----------------------(5) From equations ( 3) and ( 4), we conclude the following final equation of surface temperature [14].…”

Determining The Agricultural Drought and Desertification Intensity in Diyala Province / Iraq Using Sentinel-2 images

“…High-resolution Sentinel-2 images are accessible through the Copernicus program (10 m). Sentinel-2 imageries are used to monitor crop health, area, and productivity for regular and irregular farms due to their high spatial resolution compared to Landsat satellites, which are anticipated to produce more accurate data [10].…”

The Urban Expansion Impact on Climate Change for the City of Baghdad

“…Thus, urban expansion is a serious problem that cities suffer in general, as it represents the amount of the expanding area for the city, whether the extension is vertical and horizontal, and whether it is regular or irregular (which is represented by expansion and exploitation of lands without planning) [5]. The city of Baghdad suffers from the urban area increase in compare with the open and agricultural lands [6].This will lead to an increase in the greenhouse gases emission (resulting from burning fossil fuels used in electricity generation, production, transportation, industrialization, home heating, urban landfills, cement production, etc. ), which leads to disruption of the radiation balance, thus increasing the surface temperature and Air temperature.…”