Thailand: Time Series Analysis of Thailand Flooding 2011 (as of 22 November 2011)


This map presents a time series analysis of the dramatic southward progression of flood waters from the central provinces of Thailand towards the capital city of Bangkok, based on satellite data recorded from mid-August to 14 November 2011. Flood waters have been symbolized by color to represent the relative expansion of water from month to month. In the map, by mid-August flood waters were restricted to Northern provinces, symbolized in yellow. By mid-September, the flood waters rapidly expanded southward, symbolized in orange; by mid-October, flood waters had expanded dramatically in total area, effectively surrounding downtown Bangkok, while severely affecting most outlining populated areas; As of 14 November 2011, flood waters have further risen into the central portions of the city, while receding very little in the north of the country, indicating that it will likely take several more weeks before an appreciable decline in standing flood waters is observed. A more detailed review of very high resolution satellite imagery over Bangkok indicated that virtually all agricultural fields, significant stretches of major roads and highways as well as large residential areas remain inundated, leaving tens of thousands of residential homes and commercial businesses either partially or totally submerged. It is likely that flood waters have been systematically underestimated along highly vegetated areas along main river banks, and within built-up areas within Bangkok because of the special characteristics of the satellite data used. This analysis has not yet been validated in the field. Please send ground feedback to UNITAR /UNOSAT.