This study is to discuss the speckle statistics in terms of sea surface roughness and, specifically, in terms of near sea surface wind speed. A data set of Sentinel-1 Synthetic Aperture Radar scenes, acquired under different wind regimes, is processed using normalized intensity moments.

This study is to discuss the ability of dual-polarimetric Sentinel-1 Synthetic Aperture Radar (SAR) measurements to observe surface liquefaction occurring during earthquakes.A polarimetric bi-temporal approach is proposed that, combining pre- and co-event SAR imagery, is able to emphasize areas affected by surface liquefaction.The approach is verified using Sentinel-1 SAR scenes related to the Turkey-Syria earthquake occurred in February 2023. The approach is shown to be effective in marking areas where surface liquefaction occurred.

This study is to discuss the ability of full-resolution, i.e., speckled, Sentinel-1 single-look-complex (SLC) Synthetic Aperture Radar (SAR) imagery to monitor water-area coverage of salt ponds. Three scenarios are considered: 1) completely filled of water, 2) empty, 3) intermediate. The metric adopted to track the pond water area evolution is based on the speckle statistics and, in particular, on the departure from the fully developed speckle model.Experiments, performed using a time-series of Sentinel-1 SAR imagery collected over the salt pond "Sale ’e Porcus", Sardinia, Italy, show that Normalized Intensity Moments (NIMs) allow a good separation between the three cases under different wind conditions.

In this paper, a multi-frequency analysis of onion crop backscattering is undertaken to monitor crop phenology. Time changes of onion backscattering from C-band Sentinel-1 and X-band COSMO-SkyMed synthetic aperture radar imagery are investigated to infer information on the growth stages of onions. The test site is located in the South of Italy, Avellino province, where a sensors’ network on the ground is in place that continuously monitor soil and atmospheric parameters as temperature, moisture, wind field, etc. The test site is also equipped with an optical camera that provides real time pictures of the onion field. In this study, co-polarized (VV at C-band and HH at X-band) and cross-polarized (VH at C-band) backscattering coefficients are analyzed over the onion crop together with ancillary independent ground information. Experimental results show that the considered features have good sensitivity to the onion growth and allow identify four phenologial stages during the time span investigated in this study.

This study is to present the lesson learned during the activities related to the Italian Space Agency (ASI) funded APPLICAVEMARS project which aims at estimating sea surface wind field from L-, C- and X-band Synthetic Aperture Radar (SAR) imagery. The paper focuses on the X-band results and it describes a new approach to estimate ancillary wind direction info from the SAR image itself using neural networks.