Potential of Sentinel-1 and 2 to Assess Flooded Areas
Ghaleb Faour
*
National Center for Remote Sensing, National Council for Scientific Research (CNRS), Riad al Soloh, 1107 2260 Beirut, Lebanon
*
Corresponding author: Ghaleb Faour, National Center for Remote Sensing, National Council for Scientific Research (CNRS), Riad al Soloh, 1107 2260 Beirut,
Lebanon, Tel: +961 3 823423; E-mail: gfaour@cnrs.edu.lb
Received date: Dec 03, 2018; Accepted date: Dec 19, 2018; Published date: Dec 28, 2018
Copyright: © 2018 Faour G. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use,
distribution, and reproduction in any medium, provided the original author and source are credited.
Abstract
This paper illustrates the potential of Sentinel-1 and -2 for flood detection, mapping and characterization with the
aim of establishing policies and procedures that need to be followed in order to lower the impact of future floods.
The study area is located in Ras Baalbeck, where highlands meet vast plain area. As it relatively contains poor
infrastructures and where income is mainly based on agriculture, flood prevention and mitigation initiatives are much
needed. Multiple field visits were conducted to identify the affected areas. Based on the later and while computing
thresholds, we did classify multiple satellite imageries into damaged and un-damaged areas. The results achieved
were produced under Geographical Information System (GIS)-based software. The adopted methodology is
described followed by an analysis of future perspectives. The flooded areas extended 5.08 km2 and over two major
villages. While Sentinel-2 generated acceptable results, Sentinel-1 did not show any difference between affected
and non-affected area in term of soil water content. Still, with their high spatial and temporal resolutions, these two
satellites, particularly when coupled, could have the potential to identify the affected areas and to deliver
compensations based on it.
Keywords: Flooded areas; Sentinel-1; Sentinel-2; Lebanon
Introduction
Flood is generally regarded as the most devastated natural hazard
[1]. It is claiming the largest amount of lives and property damage
worldwide [2]. Te usage of remote sensing datasets in food-related
studies enables the reconstruction of recent history of the land surface
as well as predicting future hazardous events. Tus, several previous
studies have focused on obtaining information using remote sensing
imageries [1,3-5], with the proposal of diferent approaches. Some of
them used visible and infrared bands [6,7], Other preferred passive
microwave [8,9], or radar (active microwave) satellites [10,11].
Furthermore, various previous studies have discussed and
implemented remote sensing techniques in river stage and discharge
[12-14]. High spatial and temporal resolution satellite data such as
Sentinel-1 and -2 are particularly useful for the spatial and temporal
analysis of the fooded areas [5]. Generally, when remotely sensed
images are available before and afer such event, identifcation of these
region would be much easier.
Tis paper proposes a straightforward approach to assess and map
food-afected area. It is mainly based on the usage on both sentinel
satellites, namely Sentinel-1 and -2, having a 10-m spatial resolution
and a revisit time of six days. Te importance of such study lies in
delimiting the afected agricultural parcels which were distracted
following the food in 2018. Tis information is important for both
local government body as well as dweller to help them better shape
future policies and management plans.
Study Area
Ras Baalbek is a Lebanese local authority, which is located in
Baalbek District, an administrative division of Baalbek-Hermel
Governorate. It is located 125 km northeast of the capital Beirut. Te
average elevation in the area is 1000 m. Tis region is considered as
one of the main areas that are highly vulnerable to desertifcation due
to the intense solar radiations coupled with very low annual
precipitation. Main economic activity in the region is based on
agriculture. Furthermore, Ras Baalbek was in the recent years a hot
confict area mainly because its proximity to the Islamic State of Iraq
and the Levant (ISIS) in the nearby village of Arsal.
More recently, heavy rain in the heights of Anti-Lebanon mountain
chains on June 13th, 2018 resulted in torrential foods that took the life
of a woman and led to enormous damage in the region (Figure 1).
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ISSN: 2157-7587
Hydrology: Current Research
Faour, Hydrol Current Res 2018, 9:4
DOI: 10.4172/2157-7587.1000308
Research Article Open Access
Hydrol Current Res, an open access journal
ISSN: 2157-7587
Volume 9 • Issue 4 • 1000308