Location: Hydrology and Remote Sensing LaboratoryTitle: On the synergistic use of microwave and infrared satellite observations to monitor soil moisture and flooding Author
|Temimi, M - City University Of New York|
|Hain, C - University Of Maryland|
|Zhan, X - National Oceanic & Atmospheric Administration (NOAA)|
|Rabin, R - National Oceanic & Atmospheric Administration (NOAA)|
|Notarnicola, C - Collaborator|
|Stepinski, J - City University Of New York|
|Bonhomme, A - Collaborator|
Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 6/26/2013
Publication Date: 10/28/2013
Citation: Temimi, M., Hain, C., Zhan, X., Rabin, R., Anderson, M.C., Notarnicola, C., Stepinski, J., Bonhomme, A. 2013. On the synergistic use of microwave and infrared satellite observations to monitor soil moisture and flooding. In: Petropoulos, G. Remote Sensing of Energy Fluxes and Soil Moisture Content. Boca Raton, FL: CRC Press.
Technical Abstract: Extreme hydrological processes are often very dynamic and destructive.A better understanding of these processes requires an accurate mapping of key variables that control them. In this regard, soil moisture is perhaps the most important parameter that impacts the magnitude of flooding events as it controls the partitioning of rainfall into runoff and infiltration. It is therefore crucial to monitor the spatial and temporal variability of soil moisture conditions. In this context, remote sensing-based techniques have shown a great efficacy. Several sensors have been used to monitor hydrological processes from space, typically falling into one of the two following categories. First, microwave sensors, active and passive, have been widely used because of their high sensitivity to liquid water, which is the consequence of a significant gap between the dielectric constant of water and soil. The second category of sensors used to infer information on soil moisture and inundation includes instruments on geostationary and polar orbiting satellites, which operate in the visible and infrared (IR) wavelengths. They have been used to delineate inundated zones and infer information about soil moisture despite the negative impact of cloud coverage on these images. In the case of frequent revisit cycle, particularly in the case of geostationary instruments, image compositing and gap filling techniques may mitigate the impact of clouds. The direct sensitivity to liquid water of IR and optical sensors is relatively low in comparison to microwave sensors. However, IR observations can be obtained at significantly higher spatial resolutions. Hence, it is expected that multi-sensor approaches that combine observations from optical and IR sensors, on one hand, with observations from microwave passive and active sensors, on the other, should improve our capabilities to retrieve soil moisture and monitor extreme hydrological processes by overcoming the individual limitations of each sensor. This chapter addresses the use of satellite imagery to monitor soil moisture and inundation from space with a particular emphasis on the potential of the synergistic use of observations in the microwave and infrared domains. First, microwave-based techniques for soil moisture and inundation monitoring are discussed. Then, examples of soil moisture related products that are based on the use of IR observations are cited and discussed. Furthermore, the agreement between IR- and microwave-based products is analyzed. Finally, we present examples of blended products and demonstrate the added value of the use of observations from multiple sensors.