An Extended Neutrosophic Stepwise Weight Assessment Ratio Analysis Technique Based on GIS for Analysing Flash Floods

Abstract

Flash floods are a sudden natural hazard caused by successive heavy rains in a short period of time. The world suffers from heavy and frequent rains due to climate change. So, the risk assessment of flash floods is considered increasingly important and urgent. Egypt is considered one of the countries exposed to sudden floods resulting from heavy rains, especially in Upper Egypt. Multi-criteria techniques are widely used to study and analyze the causes and effects of natural hazards. In contrast to the traditional multi-criteria techniques used in the process of estimating flood problems, we applied neutrosophic logic in this study that has a great ability for simulating and reflecting uncertain human’s thoughts in real world problems. Our study area sits in Southeast Sohag, and it is one of the most flash floods prone regions of Egypt's Eastern Desert. This area of Sohag has suffered from frequent flash floods, with some flood events resulting in human casualties in the last decades. This study focuses on using a neutrosophic stepwise weight assessment ration analysis (N-SWARA) technique with remotely sensed data and geographical information system (GIS) for producing a flash floods hazard map. The N-SWARA technique is applied to determine the weights of various factors that related to flash flooding, including elevation, slope, topographic wetness index, distance from the stream, flow accumulation, aspect, and flow direction. The obtained weight of selected criteria used then to produce the flood hazard map (FHM) using a raster calculator tool in geographic information system. The weight of each factor calculated by using the N-SWARA multi criteria analysis method and obtained the following results: 0.39 for slope, 0.21 for elevation, 0.12 for distance, 0.08 for flow direction, 0.05 for flow accumulation, 0.09 for TWI and 0.03 for aspect.