Decision fusion for reliable flood mapping using remote sensing images

Flood extent mapping is a basic tool for flood damage assessment, which can be done by digital classification techniques using satellite imageries, including the data recorded by radar and optical sensors. However, converting the data into the information we need is not a straightforward task. One of the great challenges involved in the data interpretation is to separate the permanent water bodies and flooding regions, including both the fully inundated areas and the wet areas where trees and houses are partly covered with water. This paper adopts the decision fusion technique to combine the mapping results from radar data and the NDVI data derived from optical data. An improved capacity in terms of identifying the permanent or semi-permanent water bodies from flood inundated areas has been achieved. Computer software tools Multispec and Matlab were used

Propuesta metodológica para la estimación de zonas de inundación con información escasa por medio de descriptores geomorfométricos derivados de modelos digitales de elevación

Resumen: Se presenta una propuesta metodológica para la estimación de zonas de inundación, partiendo de información de un Modelo Digital de Elevación (MDE) y de niveles de lámina de agua. Se discuten todos los aspectos metodológicos desde la estimación de redes de drenaje en zonas planas, como la definición de los niveles de lámina de agua para diferentes períodos de retorno, atravesando por un análisis multivariado de distintos descriptores derivados del MDE con el que se pretende entender y describir la dinámica de la zona de inundación. Para la estimación de la inundación se emplea el modelo HAND al cual se le ejecutan unas variaciones para lograr mejores resultados. Los resultados son validados con información de inundaciones detectada por sensores remotos, con topografía de alta resolución y validación en campo. Además se construye una aplicación llamada FLOODEM V1.0 en la plataforma MATLAB 2012, con la que se ejecutará la metodología propuestaAbstract: A proposed methodology for estimating flood zones based on information from a Digital Elevation Model (DEM) and levels of water surface is presented. All methodological aspects are discussed from the estimation of drainage networks in flat areas, such as the definition of the levels of wáter Surface for different return periods, and passed through a multivariate analysis of different descriptors derived from DEM which aims to understand the dynamics area . To estimate the flood HAND model which will run some variations for best results is employed. The results are validated with flood information detected by remote sensing with high resolution topography and field validation. In addition an application its created called FLOODEM 2012 V1.0 in MATLAB software, which help run the proposed methodologyMaestrí

The use of satellite remote sensing for flood risk management

Over the last decades the impact of natural disasters to the global environment is becoming more and more severe. The number of disasters has dramatically increased, as well as the cost to the global economy and the number of people affected. Among the natural disaster, flood catastrophes are considered to be the most costly, devastating, broad extent and frequent, because of the tremendous fatalities, injuries, property damage, economic and social disruption they cause to the humankind. In the last thirty years, the World has suffered from severe flooding and the huge impact of floods has caused hundreds of thousands of deaths, destruction of infrastructures, disruption of economic activity and the loss of property for worth billions of dollars. In this context, satellite remote sensing, along with Geographic Information Systems (GIS), has become a key tool in flood risk management analysis. Remote sensing for supporting various aspects of flood risk management was investigated in the present thesis. In particular, the research focused on the use of satellite images for flood mapping and monitoring, damage assessment and risk assessment. The contribution of satellite remote sensing for the delineation of flood prone zones, the identification of damaged areas and the development of hazard maps was explored referring to selected cases of study