Determinação da variação da linha de costa do litoral de Aquiraz-Ceará através de ferramenta de geoprocessamento online

Abstract

The coastal zone is a highly dynamic area, acting as an interface between the continent and the ocean, marked by natural and geoecological phenomena. Its vulnerability to coastal interactions and human interventions intensifies imbalances in the natural sediment balance, generating pressures and impacts on the environment, economy, and society, with direct effects on the landscape. The valorization of coastal areas, especially since the 1970s, driven by tourism and real estate expansion, led to disordered occupation in the coastal region of Aquiraz-CE. This occupation, characterized by the construction of rigid structures, compromised sensitive ecosystems such as beaches, fluvial-marine plains, and dunes. These impacts, combined with global climate change, have exacerbated the issue of coastal erosion, altering sediment dynamics and intensifying environmental degradation. In light of this scenario, the main objective of the research was to analyze the space-time variability of coastal-marine processes along the coastline of Aquiraz-CE over a period of 9 years (2015-2024), using online geoprocessing techniques. For this purpose, the Coastal Analysis via Satellite Imagery Engine (CASSIE) tool was employed, a free web application that allows access to the Sentinel-2A satellite image catalog through the Google Earth Engine (GEE) platform. This tool enabled the calculation of the space-time variation of the coastline. The data obtained were analyzed using the Linear Regression Rate (LRR) statistical method, which stands out for allowing the full use of the historical series of coastline data, offering a comprehensive analysis of changes over time and enabling the assessment of the studied beach’s condition regarding erosion, accretion, or stability over the analyzed period. The results of the coastline variation analysis in Aquiraz-CE indicated that a total of 36% of the studied area was classified as affected by erosive processes, especially in sections 1 and 2, which were recorded in urban clusters. Therefore, these results should be used as a reference for future coastal management planning, as the data provide an overview of the current state of erosion in the studied areas.