The applications of InSAR technique for natural hazard detection in smart society

Synthetic Aperture Radar (SAR) is a potential application of remote sensing to
geological and hydrometeorological hazards. This paper presents sustainability strategies for
smart cities: the use of SAR Sentinel-1 for monitoring flood inundation and landslide hazards in
Aceh Province, Indonesia. In this study, for flood detection, we attempt to uses Sentinel-1A (S
1A) in the same direction and acquisition through polarization of Vertical transmit and Vertical
received (VV) – Vertical transmit and Horizontal received (VH) with a temporal baseline of 6
days. Those data were then analysed using the SNAP Toolbox. The results showed that the S
1A was successfully for detecting a flood inundation in which VH polarization is more sensitive
than VV. For landslide monitoring, we apply multitemporal SAR images, where one of them is
the Quasi-Persistent Scatterers (Q-PS) technique. Using ascending and descending orbit pass
results in a better velocity map where both sides of the slope are detected due to the different
sensor angle of both orbital passes. This technique has resulted in the undulating areas being
monitored well and this will also fill the gap of layover and shadowing phenomena of the slant
range SAR image. The Q-PS combinations were very effective to identify the deformation
features associated with the land movement. For a smart city, natural hazards such as landslides
and floods require continuous monitoring to ensure the potential as well as management and
mitigation of natural hazards. Therefore, the InSAR technique is one of the effective ways for
doing this strategy.