Emprego de imagens Landsat na análise temporal da linha do litoral da Praia de Ponta Grossa – Ceará

The coastal area is subject to continuous morphodynamic changes caused by processes such as, sea level fluctuations, erosive and depositional dynamics associated with the action of the waves, tides, currents flow and wind dynamics, being characterized as a very unstable environment. Due to the high economic and landscape interest of these areas, it is important to study and coastal monitoring. This article intent to study the sedimentary dynamics of Ponta Grossa beach, from time series of Landsat images. The area is located in the eastern portion of the city of Icapuí -CE, which is characterized as one of the most complex environmental systems in Ceará’s coast. The steps for processing consisted at first, in the pre-processing relating to the initial processing of the data (georeferencing of images), followed by the application of color compositions to highlight the contrast between features and the vectorization of the coastline. Thereby, it was possible to observe a very active coastal dynamic with progressive development of sedimentation and relates it to change processes that influence its dynamics. From images of time series Landsat was possible to obtain quantitative data showing that the total sediment budget in the analyzed period was positive, with higher sedimentation rates for the periods of 1997-2001 and 2005-2009, and the lowest from 1993 -2001.