Data Management Plan (Deprecated)

Dewberry contracted TRE Altamira Inc (TREA) for a historical InSAR analysis of ground displacement over the East Coast of the United States of America (U.S.A.), for the National Oceanic and Atmospheric Administration (NOAA). The area of interest (AOI) includes the major coastal cities and coastal plains and covers over 500,000 km2 (193,000 mi2).

TREAs proprietary SqueeSAR algorithm was used to process Sentinel-1 (SNT) satellite imagery acquired between January 2017 and July 2023 and the results were calibrated using the NOAA's CORS GNSS (Global Navigation Satellite System) network for the generation of vertical InSAR (SAR Interferometry) measurements.

Data covers coastal areas of the United States from Maine to Texas.

Process Steps:

• Over 3,500 Synthetic Aperture radar (SAR) images, acquired by the European Space Agency (ESA) Sentinel-1 (SNT-1) satellite over the East Coast of the United States between January 2017 and July 2023 from an ascending orbit, were downloaded for the current study. These Synthetic Aperture Radar (SAR) satellites acquired data along swathes (known as tracks), in the C-band wavelength (5.6 cm, 2.2 inches) and with a 5 x 20 meter (65 x 15 ft) ground resolution.
• The acquired SNT imagery has been processed using the SqueeSAR technique, which is the advanced multiimage InSAR algorithm patented by TREA that provides high precision measurements of ground displacement in the form of a point cloud. By analyzing a stack of SAR images acquired from the same track over an area, the SqueeSAR algorithm identifies and measures the movement of radar reflectors on the ground surface that remain visible and coherent throughout the period of the analysis. The over 3,500 images acquired along the 17 different tracks over the area of interest were processed in approximately 160 separate processing sites, and the results were combined using TREA's wide area processing chain. The analysis of the SNT imagery produced 1-D LOS InSAR measurements (i.e. away or toward the satellite along the satellite LOS) for a total of over 150,000,000 measurement points within the AOI. Due to the high variability of land cover within the area of interest, the MP density varies within the area and the lowest density was obtained over areas affected by strong decorrelation disturbances, such as swamps, areas with extensive snow coverage or dense vegetation. It is finally noted that InSAR natively provides differential displacement measurements, referring to local reference points. The absolute calibration of the LOS measurements for this was performed using the NOAA CORS network.
• The absolute calibration of the InSAR measurements, which are natively 1-D (LOS) and referred to local reference points, was performed using NOAA's CORS GNSS network. The analysis of the results highlighted a high degree of correspondence between the Vertical GNSS and Vertical InSAR data following the calibration procedure. The average displacement rate difference calculated for the 206 GNSS stations located within the area of interest is -0.1 mm/yr with a standard deviation of +/-0.3 mm/yr. Please see the report for more detailed information on calibration methodology and results.

Data is available online for downloads