Towards the Development of a Global Inundation/Flood Monitoring System Using ATMS

The objective of this study is to develop an operational global inundation/flood monitoring system using microwave brightness temperature (BT) measurements from Advanced Technology Microwave Sounder (ATMS) onboard the Suomi National Polar-orbiting Partnership (NPP) satellite. The operational tool is based on anomalies of microwave‐based soil wetness index (SWI). Swath‐wise BTs of ATMS 89 GHz and 23 GHz frequency channels are routinely downloaded from NOAA's CLASS. Each swath data is remapped to a regular grid of 40 km by 40 km using the nearest neighborhood technique to produce daily global BT maps. Global values of SWI are calculated using the difference in BT between the 89 and 23 GHz channels (Lacava et al., 2005). Using these daily SWI values, we implemented the Robust Satellite Techniques (RST) method, following Temimi et al., 2007, 2011, to calculate the Soil Wetness Variational Index (SWVI) which is dependent on the mean and standard deviation of SWIs of the same months of the previous years. These SWVI values are influenced by surface coverage variations. That capability helps to capture wet areas (inundation, flooding or very wet surface). Snow/ice on the ground were masked out using a threshold‐based approach proposed by Kongoli et al., 2006. The developed tool was also adapted to Advanced Microwave Sounding Unit (AMSU) data to investigate time-series of inundation records across the globe. The obtained maps were verified against historical flood events in Australia, India, Argentina and other parts of the world. The assessment of the performance of the developed inundation detection and monitoring system was carried out using records from the flood observatory (http://floodobservatory.colorado.edu/).

REFERENCES:

Kongoli, C., Pellegrino, P., Weng, F., Ferraro, R.R. (2006). “Evaluation of the AMSU land surface temperature algorithm for skin and shelter‐air temperature retrievals”. Extended abstract presented at the 14th Conference on Satellite Meteorology and Oceanography, part of the 86th AMS Annual Meeting, Atlanta, Georgia, January 2006.

Lacava, T., Greco, M., Di Leo, E. V., Martino, G., Pergola, N., Sannazzaro, F., and V. Tramutoli, V. (2005). "Monitoring soil wetness variations by means of satellite passive microwave observations: the HYDROPTIMET study cases". Natural Hazards and Earth System Sciences. 5, 583–592,

Temimi, M., Lacava, T., Lakhankar, T., Tramutoli, V., Ghedira, H., and Khanbilvardi, R. (2011). “A multi‐temporal analysis of AMSR‐E data for flood and discharge monitoring during the 2008 flood in Iowa”. Hydrol. Process. 25, 2623–2634.

Temimi, M., Leconte, R., Brissette, F., Chaouch, N. (2007). “Flood and Soil Wetness Monitoring Over the Mackenzie River Basin Using AMSR‐E 37 GHz Brightness Temperature”. Journal of Hydrology. Vol. 333 (2). p. 317.