Desenvolvimento de escala de classifica ̧c ̃ao e de ferramentas de previs ̃ao de ressacas para a costa S/SE do Brasil, com base no fluxo de energia das ondas

Abstract

Storm surges, phenomena of sea level rise caused by astronomical and meteoceanographic forces and amplified by wave action, pose significant risks to navigation, human life at sea, and coastal areas. In this context, the use of products derived from numerical wave prediction models is essential for identifying storm surges and issuing alerts, thereby ensu- ring maritime safety, coastal engineering, and urban planning. With the aim of enhancing storm surge prediction tools, new products based on wave energy flux (PW kW/m) have been developed. This study aimed to create a specific classification scale for each state along the South and Southeast coast of Brazil, based on the total event energy (Etotal kWh/m), the maximum observed PW , and the direction of energy propagation, using data from the Waverys reanalysis. Consequently, events with a significant wave height (HS ) above 2.5m and a minimum duration of 24 hours were categorized into five groups using the k-means method, dividing the scale into three classes: Light, Moderate, and Severe, with two subclasses for the first two categories. The validation was limited to the state of Santa Catarina, due to the absence of a national database on storm surges. The classification of 40 events indicates that the Northern and North-Central regions of Santa Catarina have suffered damage even from low-intensity storm surges, including wave heights below the utilized criterion, likely caused by the disordered occupation of the coastal region. It was also identified that the occurrence of spring tides was a determining factor in these cases, highlighting the importance of considering them in storm surge risk assessments. Finally, to assist in predictions, a structured roadmap for analyzing these events was developed, along with the Wave Monitoring System for Storm Surge Prediction (SISMOPRER), a web platform that consolidates a series of maps, diagrams, and real-time information from buoys and tide gauges, establishing itself as an integral tool for predicting such phenomena.