ROI_pac Valerie Sahakian Laura Sumiejski SIO /19/2010

What the heck is ROI_pac? Takes data Gets offsets from 2 single-look complex (SLC) images Fits 2 nd order polynomial to offsets Resample SLC images (dates) Multiply complex pixels of images Gets amplitudes

But… Amplitudes form raw interferogram – Topography – Atmosphere – Orbit – Deformation – Etc.

Refine Model Removes phase from orbit geometry – Begins flattening Calculate correlation between 2 scenes Removes topography – Calculates and removes phase from DEM Subtract models from seismic interferogram Filter noise, mask (phase variance), unwrap, etc.

Refine Model cont. Re-estimate baseline – Use topography to refine Geocoding – Unwrapped phase Change coordinates over to geographical coordinates to match DEM

Directory Hierarchy Data Directory – Data Run Directory – Copies of data –.proc file – DEM directory DEM

Choose a Location! Use EOLi – Earth Observation Link from the European Space Agency For our example we chose an area in Southern California – 35.6° N and ° W (about 36°36’ latitude and -120°18’ longitude)

Track 256 Frame 2889 Date 1: Nov. 10, 1992 Date 2: May 17, 1996

Get the Data WInSAR – Western North America InSAR Consortium – Data for western US – Members only – Data on WInSAR – Data downloadable from GeoEarthScope and Supersites

Inputs for ROI_pac: Raw Data For ERS1 and ERS2 – Assign master and slave Master = SARLEADER Slave = IMAGERY Note: these files should have the date appended to the end with the time stamp – make_raw.pl Outputs: – Raw data: date.raw – Metadata for raw data: date.raw.rsc – Reformatted orbit data: hdr_data_points_date.rsc

Inputs for ROI_pac: Parameters DEM – Digital Elevation Model SRTM data – Mosaic_srtm.pl –Rw/e/s/n magic.DEM Process File (.proc) – Int_date2_date1.proc Radar acquisition dates Pathname for magic.DEM

But… On sioprism.ucsd.edu – /data/ERS1/track/frame/orbit/ – /data/ERS2/track/frame/orbit/ ERS2_track_frame_orbit.zip Copy desired data to your directory – Run ers2roi.pl Unzips files Includes make_raw.pl Makes master and slave files Makes.proc file

Baseline Run base_roi.pl – Acceptable baseline pairs – Perpendicular and parallel baselines – Etc. Note: edit path for DEM in.proc file

process_2pass.pl Run Wait ~ 1 hour Magic happens! To see interferogram – int_date2_date1/flat/ (from after flattening) – Note: make sure you ssh using –X or -Y

Success! (sort of)

References University of Oregon, WikiRoiPac. ku.php?id=welcome ku.php?id=welcome Fielding, Eric. ROI_pac Internals: Under the Hood, UNAVCO InSAR shortcourse. August 2009.