Analysis and detection of inundation in al-Hammar and central marshes-southern Iraq using google earth engine

Abstract EN

Marches have a significant impact on the ecosystem of Iraq and provide habitat for several types of organisms.

The study area, Al-Hammar Marsh, is situated entirely south of the Euphrates, extending from near Al-Nasiriyah city in the west to the outskirts of Al-Basrah city along the Shatt Al-Arab in the east, while the Central Marshes formed between the Tigris and Euphrates rivers.

The goal of the study is to detect changes in Al-Hammar and Central marshes by using Modified Normalized Difference Water Index (MNDWI) via Google Earth Engine (GEE) cloud; considering GEE adds great value to users of remote sensing data, especially, no experts who may not be aware of the intricacies involved with data organization and large-scale computing.

Sensors Landsat 5, 7, and 8 were used and 10802 scenes were analyzed and filtered to get MNDWI by special code under the GEE environment.

Flood data were used to validate the results, which represent flood years and scarce years.

Among flood years are 1946, 1954, 1963, 1968, 1969, 1988, 1993, 1995 and 2019.

Whereas the years of scarcity were 1934, 1935, 1961, 1999, 2000, 2001, 2008, and 2009, while the year 2018 was the scariest year for Iraq.

Many factors affect the study area's inundation, such as related to the amount of rain and snow that falls in the main river basins (Tigris and its tributaries), the operation policy of the dams and reservoirs, which are built at the top of the shared rivers in Turkey, Syria, Iraq, and Iran.

In addition to the position of Iraq as a downstream country, the geological setting of marshes because they are depression areas as well as the long path for the Euphrates and Tigris rivers, and the existence of tens of regulators and agricultural lands.

By applying the Pearson equation between hydrological years data and inundation years in the study area, the value for Tigris was R2 = 0.5, which is an acceptable relationship, whereas for the Euphrates was R2 = 0.4, which is a poor relationship.