Volumetric Change Assessment and Mapping of Coastal Landform Between 2000 and 2011 Using Remote Sensing and Machine Learning Techniques

The Krishna coastal region in Andhra Pradesh and the Nagapattinam coastal region in Tamil Nadu have experienced significant alterations in their structure and arrangement as a result of human and natural interference. Affects mostly brought on by the recurrent existence of cyclones. During 2000 and 2011, both Nagapattinam and Krishna districts experienced several cyclonic events, particularly during the monsoon seasons. Coastal landforms have been extracted by thoroughly investigating many spatial data sources, including the Survey of India's topographical map, the Landsat 8-9 images, the SRTM, and ASTER DEM. Techniques for detecting changes, including topographical change detection, cross-shore profile analysis, and geomorphic change detection (GCD) using DEM of Difference (DoD), Random Forest machine learning and ANN were implemented to assess the volumetric variations in coastal landforms from 2000 to 2011. The volumetric changes of the coastal landforms were verified using field survey data collected using a GPS unit. The landforms have lowered in height by 1 to 2 m, according to the topographical change analysis, most likely as a result of cyclone activity in both coastal zones. A total of 16 profiles were surveyed for the topographical change evaluation. Investigation of cross-shore profiles for eight places shows differing degrees of loss or gain of coastal landforms for a particular coastal area. Overall volumetric changes in the coastal region of Krishna are 164.26 m3km2 due to erosion and 1047.74 m3km2 due to accretion. Land grain is 624.54 m3km2 and net land loss is 21.57 m3km2 in the Nagapattinam coastal region. In addition to offering insight into the decadal alteration in coastal settings, the study adds to a database on shore vulnerability, which will be useful to coastal managers going forward.