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7348017 
Journal Article 
Using MODIS for mapping flood events for use in hydrological and hydrodynamic models: Experiences so far 
Al-Mamun, A; Ticehurst, CN; Chen, U; Karim, SA; Dutta, D; Gouweleeuw, B 
2013 
1721-1727 
WOS:000357105901109 
Daily, or more frequent, maps of surface water have important applications in environmental and water resource management. In particular, surface water maps derived from remote sensing imagery play a useful role in the derivation of spatial inundation patterns over time and in calibrating and validating hydrological and hydrodynamic models. While MODIS data provide the most realistic means to achieve this, they are often limited by cloud cover during flooding events, and their spatial resolutions (250 - 1000 m pixel) are not always suited to small river catchments. This paper tests the suitability of MODIS for providing daily surface water maps, both spatially and temporally, across a range of Australian catchments. This study shows that MODIS is suitable for capturing both medium and large flood events, but lacks the detail around the edge of a flood or along narrow water features where it tends to underestimate water extent. Compared to a Landsat water map, the MODIS water maps have shown a strong-to-moderate statistical agreement. Soils are sometimes mapped as wet when they are not, possibly due to confusion with moisture in the soil and/or soil colour. Flooding under dense vegetation is often invisible to MODIS or any other optical remote sensor. Care must also be taken when using MODIS data along the edge of the image swath where the water extent can be underestimated. The view angle, or range distance from sensor to pixel, influences the amount of water that can be mapped, as is demonstrated with a permanent water body. On a temporal scale, cloud cover often inhibits the use of MODIS imagery at the start and lead-up to the peak of a flood event, but there are usually more cloud-free data to monitor the flood's recession. MODIS surface water maps are sensitive to the dynamics of water movement when compared to flow gauge data. Given their temporal and spatial characteristics, the MODIS sensors can provide useful information for hydrodynamic modelling, and do appear to be the best available product for mapping inundation extent and its change dynamics at large regional/basin scales. 
Optical remote sensing; surface water mapping; flood inundation