HYDRODYNAMIC MODELING OF THE LOWER AMAZON: UNDERSTANDING FLOW PATTERNS AND DYNAMICS

Código

XXV-SBRH0678

Autores

Monica Frickmann Young Buckmann, Paulo César Colonna Rosman, Jeffrey Edward Richey

Tema

STE07 - Desafios e Estratégias de Resiliência em Cidades Costeiras

Resumo

Hydrodynamic modeling of the Lower Amazon is a complex process aimed at understanding and predicting the hydrological characteristics of this region. The lower reaches of the Amazon present a highly intricate geography, with two large and several small tributaries entering, an extensive flood-plain, multiple channels, and islands, including an island the size of Switzerland. There is pro-nounced tidal regime, of about 3 m at Macapá, causing flow reversal, and detectable 900 km up-stream as far as Óbidos. To represent the dynamics of this region, we have selected the model SisBaHiA, (Sistema Base de Hidrodinâmica Ambiental, www.sisbahia.coppe.ufrj.br). SisBaHiA, developed at UFRJ, has hydrodynamic models designed to represent flows in water bodies with complex geometry, as usual in natural systems. Flows with horizontal movement scales at least 20 times larger than the depth can be considered as shallow water flows. In this situation the pressure field can be considered as almost hydrostatic. The amazon estuary fits in this case, in addition, it tends to be vertically homogeneous. It justifies the application of a vertically integrated hydrody-namic model, that is, two-dimensional horizontally, also known as 2DH. By understanding and pre-dicting hydrological characteristics such as water levels, hydrodynamic modeling assists in water resource management, flood prevention, environmental impact assessment, and the planning of wa-ter infrastructure projects. In this article, we explore aspects of the hydrodynamics of the Lower Amazon, including the influence of river flow and tide on the flow dynamics and current reversal limits, considering the hydrological cycle in 2020.