Analysis of the Shoreline Variation in the Area Between Peroba and Redonda's Beaches in Icapuí-Ceará, Brazil, Based on Satellite Images Using DSAS

Abstract

Icapuí, the municipality's coastal zone, is made up of sandy beaches, cliff formations, dunes, and a vast stretch of marshes. Due to their interactions with water, land, and air, these regions are highly active; erosion or deposition may occur as a result of this interaction. Constant losses of sediments, especially in cities, are a concern that has been the focus of study using various methods and tools to understand coastal dynamics, both short, medium, and long term. The understanding of the change in the shoreline between Peroba and Redonda beaches in Icapuí, based on satellite images, was obtained using Digital Shoreline Analysis System at a time scale ranging from 2005 to 2020. According to the results, from 2005 to 2010, the shoreline trended stably at 62.52 percent and regressed by 37.48 percent. Between 2010 and 2015, it stayed constant at 51.68 percent before progressing by 46.94% between 2015 and 2020. The stability of the line decreased to 13.22 percent with a regression of 86.78% between 2015 and 2020. The data provided by the Taxa do Ponto Final and Linear Regressions between 2005 and 2020, -0.61 and -0.70 mm/year respectively, indicate that the coastline line remained relatively stable at about 90% (4.570 m) and 84% (4.470 m).

Keywords: Coastal erosion; accretion; retrogradation; progradation.