A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Identification and Mapping of 2019 Flood Extents Using Sentinel-1 A Images: A Case of Barpeta District, Assam
During the time of a crisis, the foremost initiation is decision making and minimizing its extent, for which, real-time crucial information is required. In flood scenarios, it is always challenging to get quick, efficient, and reliable information due to severe weather conditions and disruption in all means of communication. Even though optical radar image reveals various earth surface information, it has limitations during severe weather conditions, whereas in the case of synthetic aperture radar (SAR), the emitted microwaves can acquire remotely sensed high-resolution real-time spatial information, in spite of the fog, mist, or cloudy conditions during monsoon season. The SAR sensors are highly sensitive to the roughness and wetness of the surfaces; and as it is an active satellite system, it can acquire ground information at any hour of the day. The near real-time SAR information can help in swift mapping of flood situations helping in decision making, responding, and minimizing massive loss of life and assets. Therefore, SAR data has been preferred for the study. In this paper, the potential of Sentinel-1 A, high-resolution C band image, along with GIS, is explored, taking the ground scenario of the 2019 Assam flood into consideration. A series of SAR crisis images (during the flood) of four days, that is 14th, 21st, 26th July and 7th August 2019, and one archived image (non-flooded time), 5th December 2019, were selected as candidate images. They were processed and analysed, using ESA SNAP Sentinel-1 Toolbox and GIS. The spatial extent of flood and inundation of built-up areas have been estimated for this period. The study found that the variation was approximately 219 km2 in archive time to 1089 km2 on the extreme situation that is on 26th July 2019. The flood situation improved from 14th to 21st and again intensified on 26th July. Gradually towards 7th August, the condition was improved, affecting only about 78 km2 of built-up area. The findings of the study can help in understanding the miserable situations and flood extents, decision making, minimize the impact of floods, and lead to risk reduction and better management during disastrous situations.
Identification and Mapping of 2019 Flood Extents Using Sentinel-1 A Images: A Case of Barpeta District, Assam
During the time of a crisis, the foremost initiation is decision making and minimizing its extent, for which, real-time crucial information is required. In flood scenarios, it is always challenging to get quick, efficient, and reliable information due to severe weather conditions and disruption in all means of communication. Even though optical radar image reveals various earth surface information, it has limitations during severe weather conditions, whereas in the case of synthetic aperture radar (SAR), the emitted microwaves can acquire remotely sensed high-resolution real-time spatial information, in spite of the fog, mist, or cloudy conditions during monsoon season. The SAR sensors are highly sensitive to the roughness and wetness of the surfaces; and as it is an active satellite system, it can acquire ground information at any hour of the day. The near real-time SAR information can help in swift mapping of flood situations helping in decision making, responding, and minimizing massive loss of life and assets. Therefore, SAR data has been preferred for the study. In this paper, the potential of Sentinel-1 A, high-resolution C band image, along with GIS, is explored, taking the ground scenario of the 2019 Assam flood into consideration. A series of SAR crisis images (during the flood) of four days, that is 14th, 21st, 26th July and 7th August 2019, and one archived image (non-flooded time), 5th December 2019, were selected as candidate images. They were processed and analysed, using ESA SNAP Sentinel-1 Toolbox and GIS. The spatial extent of flood and inundation of built-up areas have been estimated for this period. The study found that the variation was approximately 219 km2 in archive time to 1089 km2 on the extreme situation that is on 26th July 2019. The flood situation improved from 14th to 21st and again intensified on 26th July. Gradually towards 7th August, the condition was improved, affecting only about 78 km2 of built-up area. The findings of the study can help in understanding the miserable situations and flood extents, decision making, minimize the impact of floods, and lead to risk reduction and better management during disastrous situations.
Identification and Mapping of 2019 Flood Extents Using Sentinel-1 A Images: A Case of Barpeta District, Assam
Advances in Sustainability sci. & technol.
Bhattacharjya, Rajib Kumar (editor) / Talukdar, Bipul (editor) / Katsifarakis, Konstantinos L. (editor) / Chetia, Leena (author) / Paul, Saikat Kumar (author) / Dhawale, Richa (author) / Joy, Nayana Merin (author)
2022-06-18
9 pages
Article/Chapter (Book)
Electronic Resource
English