MOSART-inundation

Abstract

Flood events have impacts on the exchange of energy and matter (e.g., vapor, carbon dioxide, methane, etc.) between land-river and land-atmosphere, hence potentially affecting the climate. The Amazon River basin is the world’s largest river basin. Seasonal floods occur at the Amazon Basin each year. This basin is characterized by flat gradients which cause evident backwater effects in the river dynamics. In addition, there exist large uncertainties in the dataset (e.g., river hydraulic geometry, surface topography, etc.) necessary for inundation modeling. These factors contribute to the difficulty in simulating the flooding processes over this basin. We have developed a large-scale inundation scheme in the framework of the MOSART river routing model. Both the kinematic wave and the diffusion wave routing methods are implemented in the model. A new process-based algorithm is designed to represent the river channel – floodplain interaction. We also made effort to handle the uncertainties in the input dataset. The performance of this inundation scheme is evaluated against satellite and in situ observations at the Amazon Basin.