High resolution ground deformations monitoring by COSMO-SkyMed PSP SAR interferometry

Transcription

1 High resolution ground deformations monitoring by COSMO-SkyMed PSP SAR interferometry Mario Costantini e-geos - an ASI/Telespazio Company, Rome, Italy mario.costantini@e-geos.it

2 Summary COSMO-SkyMed satellite constellation Synthetic aperture radar (SAR) interferometry principles and applications E-GEOS PSP-IFSAR processing technology and products/services Validation and comparison between ERS/Envisat and COSMO-SkyMed Examples of applications: Buildings and structures stability monitoring Subsidence and extraction sites monitoring Landslides monitoring Earthquakes and volcanoes A national scale project: analysis of the whole Italian territory with ERS/Envisat SAR data Conclusions Page 2

3 COSMO-SkyMed satellite constellation Page 3

4 COSMO-SkyMed constellation Four satellites equipped with high resolution X-band synthetic aperture radar (SAR) sensors Cosmo 1 launch June 8, :34 GMT Cosmo 2 launch December 9, :31 GMT Cosmo 3 launch October 25, :28 GMT Cosmo 4 launch November 6, :20 GMT Page 4

5 COSMO-SkyMed imaging modes Flight Direction Swath HUGEREGION WIDEREGION HIMAGE PINGPONG MODE-2 Resolution 100 m 30 m 3 m 15 m 1 m Swath 200 km 100 km 40 km 30 km 10 x 10 km Strip length ~2,000 km ~2,000 km ~2,000 km ~2,000 km SCANSAR STRIPMAP SPOTLIGHT Page 5

6 Reliability & Continuity COSMO-SkyMed X-band CSK-1 launched 8 June 2007 CSK-2 launched 9 December 2007 CSK-3 launched 25 October 2008 CSK-4 launched 6 November 2010 COSMO 2 nd Generation Page 6

7 SAR interferometry principles and applications Page 7

8 SAR interferometry basic principles Synthetic aperture radar (SAR) interferometry is a powerful technique to determine the topography of the observed scene and possible slow surface movements due to subsidence, landslides, seismic and volcanic phenomena. ΔR top 1 st acquisition 2 nd acquisition R1 Δt 35 days (ERS/ENVISAT) Δt 1 days (COSMO-SkyMed) (8 acquisitions per month) R2 Extraction of this information requires a complex The technology: interferometric phase between the two SAR images contains three contributions: The sparse points with coherent signal Contribution related to the three-dimesional location (corresponding of the target to buildings, w.r.t. the rocks, two bare known soil) must observation be found as positions. part of the processing A SAR provides a twodimensional image of the scene (along track position and range sensor-target coordinates). The phase contributions corresponding to Contribution related to the atmospheric propagation atmosphere, delays target position and displacement must be separated using several acquisitions Contribution related to the terrain displacement The phase is along measured the line ambiguously of sight (modulo 2p) and must be unwrapped ΔR disp Area subject to a deformation. Page 8

9 SAR interferometry applications Pipelines Building Critical sites Railway infrastructures Dams Analysis and monitoring of ground deformations Subsidence phenomena Landslides Critical structures Oil&Gas Mining activities Earthquakes Highways Volcanic phenomena Page 9

10 PSP technology and e-geos products/services Page 10

11 PSP- IFSAR technology We have developed a proprietary advanced processing technology (PSP-IFSAR) with original algorithms, among which: Persistent scatterer pair (PSP) method for selection and analysis of coherent points Exploiting only the relative signals between pairs of nearby points, it is intrinsically not affected by atmosphere Redundant finite difference integration and phase unwrapping Exploiting highly redundant information from a non-planar graph (2D or multitemporal 3D), guarantees more reliable and accurate solutions The processing chain runs on a parallel high performance computer (HPC) system Successfully validated and used in massive productions, with ERS/Envisat and high resolution COSMO-SkyMed SAR data Page 11

12 COSMO SkyMed for persistent scatterer interferometry High resolution X-band SAR proved to be very good for persistent scatterer interferometry: Very high density of persistent scatterers (tens of thousands per km 2 in urban areas already with StripMap images) Measurement of differential displacements within the same structure (i.e. a building, a bridge, a dam) High sensitivity to displacements (short wavelength) COSMO-SkyMed constellation of 4 satellites has some unique capabilities: Very good revisit time (up to 8 acquisitions per month with the same look angle necessary for interferometry) Measurement of fast movements Long series of acquisitions in a short time High acquisition capabilities (up to 2000 images per day) Page 12

13 SAR interferometry e-geos portfolio - e-geos SAR interferometry portfolio includes: SAR data High level products: database of ground deformation measurements (to be integrated in GIS environment for analysis and interpretation of the results by the final user) Services: analysis and monitoring of the ground deformations, including analysis and interpretation of the observed phenomena Satellite acquisition Ground deformation measurements PSP-IFSAR processing Ground deformation analysis service SAR data High Level Products: SAR derived data Services: Integrated data & analysis reports Product Fruition (Image processing applications or GoogleEarth/GIS ready data WebGis access) Page 13

14 Validation and comparison between ERS/Envisat and COSMO-SkyMed Page 14

15 Beijing, China ENVISAT PSP-IFSAR analysis Page 15

16 COSMO-SkyMed vs ENVISAT PSP-IFSAR analysis Page 16

17 Displacement (mm) COSMO-SkyMed vs ENVISAT PS mean velocities: area 1 CSK vs ENVISAT displacement ENVISAT COSMO /14/07 02/22/08 06/01/08 09/09/08 12/18/08 03/28/09 07/06/09 10/14/09 01/22/10 05/02/10 08/10/10 Time (days) Page 17

18 Beijing subsidence COSMO-SkyMed PSP-IFSAR analysis 2132 analysis --January 2009November 2010 months analysis -January January 2009August months months analysis 2009October 2009 Contour levels showing the displacement evolution Page 18

19 Beijing subsidence 3D view COSMO-SkyMed PSP-IFSAR analysis Page 19

20 Validation with optical leveling from Beijing Institute of Surveying and Mapping No. Leveling (mm) PSP (mm) Leveling-PSP (mm) Comparison between PSP- IFSAR and optical levelling measurements march march Mean = -1.2 mm, Std dev. = 1.9 mm Velocity accuracy: 0,5 mm/year in 4 years COSMO-SkyMed PSP-IFSAR ground deformation measurements: Millimetric accuracy (almost an order of magnitude more precise than with C-band Envisat data) Up to more than 30 thousand PS/km 2 with stripmap data (two orders of magnitude more than with Envisat data) Page 20

21 Comparison ERS/COSMO-SkyMed PSP-IFSAR processing - ERS data ( ) Descending pass PSP-IFSAR processing - CSK StripMap data ( ) Descending pass Page 21

22 Comparison Envisat/COSMO-SkyMed A3- Napoli- Salerno Interferometric analysis performed by COSMO- SkyMed StripMap data Ascending acquisition mode A3- Napoli- Salerno Interferometric analysis performed by ENVISAT data Ascending acquisition mode Page 22

23 Displacement (mm) Volcanic bradyseism, Naples region, Italy PSP-IFSAR analysis and validation Mean velocity (mm/year) < Levelling > ERS ENVISAT Mean velocity (mm/year) < ERS /07/90 01/31/93 10/28/95 07/24/98 04/19/01 01/14/04 10/10/06 07/06/09 04/01/ Time > ENVISAT Page 23

24 Examples of buildings and structures stability monitoring Page 24

25 The bridge is completely designed by the PSs. It allows to monitor its displacement in several points of the structure. PSP analysis of a bridge, 3D view COSMO-SkyMed StripMap February December 2010 Railway Page 25

26 Subsidence along the Shanghai subway line 9 COSMO-SkyMed PSP-IFSAR analysis Xiaonanmen Lujiabang Road Page 26

27 Railway tracks e-geos is monitoring railways tracks for Russian Railway company (NIIAS/RZD) by COSMO-SkyMed PSP SAR interferometry Black Sea Area of interest COSMO-SkyMed Stripmap coverage of the area of interest Page 27

28 Landslides along the railway line PSP-IFSAR analysis 3D view Areas affected by landslides Railway Page 28

29 Landslides PS mean velocities 3D view Railway Page 29

30 Highway stability analysis PSP-IFSAR ENVISAT ( ) Highway Rome-Fiumicino Mean velocity (mm/year) G.R.A. Page 30

31 Tuapse Harbor COSMO-SkyMed StripMap Dec Oct 2010 Page 31

32 Industrial site, Tuapse, Russia Cosmo-SkyMed PSP-IFSAR analysis Page 32

33 PSP analysis of an industrial site Page 33

34 PSP-IFSAR analysis of an antenna COSMO-SkyMed data- December 2008-October 2010 The high PSs density allows to define completely the antenna structure. For each point a displacement measurement estimation is provided Tuapse, Russia Page 34

35 Displacement (mm/year) Displacement (mm/year) Dam monitoring ENVISAT ( ) PSP-IFSAR analysis Landslide system detected close to the dam /9/ /1/ /5/ /10/ /2/2008 6/7/2009 Time (days) /9/ /1/ /5/ /10/ /2/2008 6/7/2009 Time (days) Page 35

36 Displacement (mm) Shanghai, China COSMO-SkyMed PSP-IFSAR analysis for building stability High density of Measurement points over a single building /02/ /06/ /09/ /12/ /03/ /07/ /10/ /01/2010 Time (day) Page 36

37 The China World Trade Center,Beijing COSMO-SkyMed PSP-IFSAR analysis 3D view Page 37

38 Subsidence and extraction sites monitoring Page 38

39 Romagna, Italy, subsidence monitoring ENVISAT PSP-IFSAR analysis Gas extraction ERS ASC Offshore platforms Water extraction Page 39

40 Subsidence due to Gas Extraction activities Ravenna, Italy. Terrain stability analysis performed by ENVISAT data ( ). Monitoring of terrain displacement due to gas extraction activities: subsidence effect along the coastal area. Page 40

41 Extraction area in Emilia Romagna, Italy Envisat Emilia Romagna extraction area Page 41

42 Gas extraction sites in Emilia Romagna, Italy PS mean velocities, Envisat Page 42

43 Gas extraction sites of Cotignola, Ravenna - Italy PS mean velocities, Envisat Page 43

44 Gas extraction sites of Formigine, Modena - Italy PS mean velocities, Envisat Page 44

45 Oil & Gas extraction sites of Correggio, Reggio Emilia - Italy PS mean velocities, Envisat Page 45

46 Extraction area in Sicilia, Italy Envisat Sicilia extraction area Page 46

47 Oil extraction sites of Gela, Caltanissetta - Italy PS mean velocities, Envisat Page 47

48 Extraction area in Basilicata, Italy Envisat Basilicata extraction area Page 48

49 Oil extraction site Tempa d Emma, Potenza - Italy PS mean velocities, Envisat Page 49

50 Gas extraction site Appia, Matera - Italy PS mean velocities, Envisat Page 50

51 Gas extraction sites of Policoro, Matera - Italy PS mean velocities, Envisat Non-active gas site Extraction sites Page 51

52 Oil & Gas extraction sites of Pisticci, Matera - Italy PS mean velocities, Envisat Page 52

53 Travertine quarry, Guidonia (Rm): ENVISAT ascending data Guidonia, Rome. Envisat ( ) Page 53

54 Landslides monitoring Page 54

55 Lazarevdkoye, Russia, landslide COSMO-SkyMed PSP-IFSAR analysis Mean velocity (mm/year) < > 17.5 Page 55

56 Tuapse, Russia, landslide COSMO-SkyMed PSP-IFSAR analysis Page 56

57 Valdisotto valley, Alps, Italy ERS PSP-IFSAR landslide analysis Valdisotto valley, Alps, Italy. Page 57

58 PSP-IFSAR landslide analysis ENVISAT ASC ENVISAT DESC Using two acquisition geometries (ascending and descending) two components of the ground displacement are measured, and vertical and east-west displacements can be determined. Page 58

59 Earthquakes & Volcanes Page 59

60 Etna volcano ENVISAT ( ) PSP-IFSAR analysis Page 60

61 Christchurch (New Zealand) earthquake, 2011 co-seismic interferometric analysis In the city of Christchurch, there are many incoherente points due to the damages of the earthquake In the image, it is evident the fault line near the city. The co-seismic interferogram can be used to know the earthquake mathematical model Christchurch area, ~40 x 40 km 2 COSMO-SkyMed HIMAGE SAR data: Ascending geometry Positive displacement Ground resolution: 3x3 m 2 images: 19 Feb Feb 2011 Multilook factor: 5x5 Negative displacement -π 0 < π > 24 [rad] [cm] < > 24 [cm] Page 61

62 PSP-IFSAR analysis massive productions Page 62

63 Some examples from a nation-wide PSI analysis project The PST-A/2 project, commissioned by the Italian Ministry of the Environment, is a huge project aimed at providing terrain displacement measurements by SAR interferometry over an entire national territory (Italy, 300,000 Km 2 ) Analysis of the whole period covered by data available for interferometry: (ERS) and (Envisat) Processing of the whole ESA ERS/Envisat archive over Italy (about 15,000 images), by TRE and e-geos TO BE EXTENDED WITH COSMO-SKYMED DATA Page 63

64 Italy ERS descending data Page 64

65 Italy ERS ascending data Page 65

66 Italy ENVISAT descending data (to be completed by beginning 2012) Page 66

67 Italy ENVISAT ascending data (to be completed by beginning 2012) Page 67

68 Conclusions (1 of 2) COSMO-SkyMed satellite constellation SAR interferometry principles and applications E-GEOS PSP-IFSAR processing technology: Persistent scatterer pair (PSP) technique: an advanced approach to persistent scatterer pair interferometry Redundant LP finite difference integration and phase unwrapping: improved accuracy and reliability of results High performance parallel processing system: large scale productions E-GEOS SAR interferometry product portfolio SAR data PSP-IFSAR data ready for analysis on GIS / Google Earth Ground deformation analysis service Validation and examples and of application of PSP-IFSAR analysis for monitoring of building and structures, subsidence and extraction sites, landslides, earthquakes and volcanoes, a national scale project Page 68

69 Conclusions (2 of 2) COSMO-SkyMed SAR interferometry enables ground deformations measurements with: High temporal frequency up to 8 measurements per months with COSMO-SkyMed constellation Unprecedented spatial density tens of thousand measurements per km 2 with stripmap COSMO-SkyMed data and up to one million per km 2 with spotlight PSP-IFSAR technology proved to guarantee: Accurate deformation measurements Accurate 3D localization of the measurements High density of measurements Reliability and robustness to noise and outliers Massive automatic productions Page 69