Terrafirma monitoring and mapping landslide services for Europe based on InSAR satellite data

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1 Department of Earth Sciences CENTRE OF COMPETENCE OF THE CIVIL PROTECTION DEPARTMENT PRESIDENCY OF THE COUNCIL OF MINISTERS Terrafirma monitoring and mapping landslide services for Europe based on InSAR satellite data Pancioli V., Casagli N., Righini G., Corazza A., Putrino P.

2 Working group and expertise Department of Earth Sciences - University of Firenze Responsible: Prof. Nicola Casagli Interpretation of remote sensing data: Valeria Pancioli & Gaia Righini Italian National Department of Civil Protection End user - support and data validation: Angelo Corazza & Paolo Putrino

3 Objectives To illustrate the landslide service in the framework of Terrafirma. To present some examples of the Landslide Inventory product. To present some examples of the Landslide Monitoring product. To highlight the User s role and feedback.

4 TERRAFIRMA landslide service Operational service providers and value adders: UNIFI TRE GAMMA ALTAMIRA ISTITUT DE GEOMATICA End Users: Italian Civil Protection Italian local agencies in charge of risk management Swiss Federal Office of Environment IGME (Spain) IGME (Greece)

5 Landslide products Landslide Inventory (LSI) and Landslide Monitoring (LSM) PSI products are made from integration of VHR optical data (air-photo, SPOT5, Ikonos/Quickbird), of radar data acquired by three ESA missions; ERS-1/2 ( ), and ENVISAT (2002- present), giving motion measurements from 1992 to now. LSI Product: upgrade of a landslide inventory map produced through the integration of radar data and optical VHR data LSM Product: long term PSI monitoring of ground movements induced by a specific slow-moving landslides

6 TERRAFIRMA landslide sites Terrafirma is delivering products for areas of Europe with a high landslide risk. By 2009, 17 landslide products will be completed, interpreted and activated. Lumnez (LSM) Graubünden Canton (LSI) Gaggio Montano (LSM) S. Stefano d Aveto (LSM) Reno basin (LSI) Ancona (LSM) Biferno basin (LSI) Gorgoglione(LSM) Corinth Gulf (LSI) UNIFI SITES (11) Frazzanò(LSM) Sites processed Sites in processing Other value adder providers Calabrian basin (LSI)

7 USERS involved The users of the services are Civil Protection Authorities at national and local level, regional agencies for the protection of the environment and municipalities Italian National Civil Protection Department Italy Institute of Geology & Mineral Exploration Greece REGIONE CALABRIA Basin Autority Italy REGIONE LIGURIA Environmental Dept. Italy REGIONE MARCHE Civil Protection Italy Federal Office for the Environment Switzerland Ancona Municipality Italy REGIONE EMILIA ROMAGNA Civil Protection Italy

8 Methodology Acquisition of Radar ERS - ENVISAT datasets Acquisition of Ancillary data and Optical images GIS Environment GIS Environment Homogenization User Input and Recomendation Homogenization Radar Interpretation ERS (92-02) ENVISAT (03- now) Photointerpretation Aerial photo + Topographic map Field surveys LSI and LSM products

9 Landslide Inventory products Graubünden Canton Reno basin Biferno basin Corinth Gulf Calabrian basin LSI test sites

10 Landslide Monitoring products Lumnez Gaggio Montano S. Stefano d Aveto Ancona Gorgoglione Frazzanò LSM test sites

11 User: Swiss Federal Office of Environment LSI: GRAUBÜNDEN CANTON, Switzerland Graubünden Canton: 3828 km² Landslide prone area characterized by fine-grained rocks such as the Flysch formations, many of the largest rock and earth slides are well known Landslide Inventory is not available

12 Ortophoto - copyright Swiss Federal Office of Environment Input Data IPTA datasets processed by GAMMA Remote Sensing supplier Digital elevation model (Dem) 25 m pixel resolution Topographic map 1: scale - copyright Swiss Federal Office of Environment

13 Graubuenden Canton: InSAR data IPTA Investigated area: 3828 km 2 (UL: 47 N, 9 E - LR: 46 N,10 E) 120 images ERS (40 ascending 80 descending) ( ) 20 images ENVISAT (10 ascending -10 descending) ( ) Data processing by GAMMA Remote Sensing

14 IPTA datasets Department of Earth Sciences CENTRE OF COMPETENCE OF THE CIVIL PROTECTION DEPARTMENT PRESIDENCY OF THE COUNCIL OF MINISTERS Data processing by GAMMA Remote Sensing

15 Landslide Classification Landslide classification is based on the medium velocity computed for every landslides from ERS/ENVISAT IPTA data Terrafirma Landslide Inventory: mm/y moderate 5-10 mm/y slow 2-5 mm/y very slow 0-2 mm/y stable Under investigation Information by FOEN

16 TERRAFIRMA Landslide Inventory Department of Earth Sciences CENTRE OF COMPETENCE OF THE CIVIL PROTECTION DEPARTMENT PRESIDENCY OF THE COUNCIL OF MINISTERS

17 Field validation

18 Field validation

19 Analysed area: 3828 km 2 Results Number of landslide identified: 112 Landslide area: km 2 (7.1%) IPTA that has given landslide information 7264 (10.7 %) Classes Number of landslides Landslide interested area (km²) Moderate Classes frequency distribution Slow Very slow Stable Under investigation Information by FOEN ,8% 3,6% By number 8,9% 5,4% 23,2% mm/y Moderate 5-10 mm/y Slow 2-5 mm/y Very slow 6,5% 17,1% By area (km²) 16,3% 12,3% 49,1% 0-2 mm/y Stable Under investigation Information by FOEN 4,5% 43,3%

20 User: Italian Civil Protection Department LSI: Biferno basin, Italy Biferno basin: 800 km² Landslide prone area characterized by calcareous marls flysch formation and clayey formation, almost all the phenomena are represented by roto-translational, complex and flows. In January 2003, the area has been affected by a flood caused by intense and prolonged precipitation, that re-activated several preexisting landslides. Landslide Inventory is available

21 Input data Geology map

22 PS ERS ascending PS ,5 PS/km 2 Data processing by TRE

23 PS ERS descending PS ,6 PS/km 2 Data processing by TRE

24 PS ENVISAT ascending PS ,6 PS/km 2 Data processing by TRE

25 PS ENVISAT descending PS ,2 PS/km 2 Data processing by TRE

26 Activity matrix ERS ( ) mm/y 2 10 ERS missing mm/y STABILIZED ENVISAT ( ) 2 10 ENVISAT missing V 00 V 01 V 02 V 0# DORMANT ACTIVE Extremely slow ACTIVE Very slow INACTIVE 2000 ACTIVE 2000 Extremely slow V 10 V 11 V 12 V 1# ACTIVE 2000 Very slow V 20 V 21 V 22 V 2# INACTIVE 2007 N.C. V #0 V #1 V #2 V ##

27 Field validation CASTELMAURO GUARDIALFIERA LARINO CIVITACAMPOMARANO CASACALENDA RIPABOTTONI

28 Castelmauro New Landslide Activity: modified Boundary: modified New Landslide

29 Guardialfiera: PS ERS

30 Guardialfiera: PS ENVISAT New Landslide Activity: confirmed Boundary: modified New Landslide

31 Terrafirma landslide inventory

32 Terrafirma landslide inventory database - Geometric boundary - Data origin - State of activity - N PS ERS and ENVISAT - Velocity statistical data

33 Terrafirma Inventory results The final database consists of 3093 landslides 261 of which (8,5%) have been modified or added by means PS information Number of landslides Landslides interested area (km²) New landslides 95 10,3 Confirmed landalsides 17 2,8 Modified landslide activity 32 4,8 Modified boundaries 81 27,6 Modified boundaries and activity 36 5,1 By number new landslides By area (km²) 13,8% 36,4% confirmed changed activity 10,0% 20,3% 5,6% 31,0% 12,3% 6,5% changed boundaries changed boundaries and activity 54,6% 9,5%

34 LSM: GORGOGLIONE, Italy Basilicata Region: Basilicata Hydrographic basin: Agri Altitude a.s.l.: 820 m m Geology: Gorgolgione Flysch (Tortonian siliciclastic turbidite formation) villages affected: 1 citizens: Type: earth slides State of activity: active Dimension: 0.33 km 2

35 Gorgoglione Landslide Gorgoglione is affected by an ancient landslide, re-activated during the Irpinia earthquake (1980). An acceleration of the ground movements between late 2003 and the summer 2004 induced the evacuation and the demolition of several buildings. Field surveys (National Group for Geo-hydrological Disaster Prevention of the Italian funded by the CPA), highlighted the presence of a general slope instability in the portion of the village located below Piazza Zanardelli. After the acceleration in situ instrumentations has been installed by the Gorgoglione municipality, but the causes of the slope movements are still under investigation.

36 Damages Damaged pavement and repaired works in the main square

37 Gorgoglione: InSAR Data APSA Investigated area: 0.33 km images ERS (44 ascending 84 descending) ( ) 23 images ENVISAT ascending ( ) Data processing by TeleRilevamento Europa

38 Datasets ERS-ENVISAT Department of Earth Sciences CENTRE OF COMPETENCE OF THE CIVIL PROTECTION DEPARTMENT PRESIDENCY OF THE COUNCIL OF MINISTERS Hazard map Very high High Medium Low Data processing by TRE

39 PSI analysis Hazard map Very high High Medium Low The PSI analysis performed confirm the above information highlighting the presence of ground displacement perfectly correspondent to the portion where damages were registered

40 Results of PSI analysis PS analysis has allowed to redraw correctly the landslide boundaries, in particular to define the landslide crowns. Is evident a clear line of demarcation between PS with null velocity and PS with high velocity values.

41 20,00 0,00-20,00-40,00-60,00-80,00-100,00-120,00-140,00-160,00-180,00-200,00 Time Series: ERS - ENVISAT ERS ascending (A08F5) ENVISAT ascending (A2FW4) no data 23/05/ /08/ /11/ /02/ /04/ /07/ /10/ /01/ /04/ /06/ /09/ /12/ /03/2007 displacement (mm) ERS V = - 13,14 mm/y ENVISAT V = - 22,01 mm/y

42 Comparison with Topographic Data Vertical displacement Topographic levelling (nov 2004-may 2005) Average vertical displacement = 8.6 mm

43 Time Series ENVISAT vs Topographic Data Envisat ascending Code A2FPY 0,00-10,00-20,00-30,00 Topographic levelling Vertical component of ENVISAT acquisition V = mm/y Average displacement of topographic levelling = 8.66 mm ( v = 15,0 mm/y ) -40,00-50,00-60,00 V = mm/y -70,00-80,00 14/11/2007 displacement (mm) 10/12/ /06/ /01/ /11/ /08/ /04/ /02/ /09/ /03/ /10/ /04/2007

44 Geologic section - InSAR data analysis The upper part of the slope is characterized by the presence of a clear line of demarcation between PS with null velocity and PS with high velocity values. This suggest an advancing phenomenon without any retrogressive activity; the information is consistent with the geological cross section and with the slope instability behaviour since its re-activation in m 800 m 750 m 0 velocity (mm/y) Envisat ascending ERS descending ERS ascending

45 User s role FROM the definition/validation of the PRODUCTS TO the definition/validation of the SERVICE User as a PRODUCT co-designer Site selection requirements User as a SERVICE observer, tester & validator

46 User s evaluation What applications Practical benefits BENEFITS Decision process? How much is saved?

47 User s feedback For what applications would you use Terrafirma products? What are the practical benefits of Terrafirma products? The product can be used following emergencies induced by landslides to understand the general stability conditions of the area before the event, or as a basic information layer to be used along with other thematic layers to carry out field surveys following requests coming from local or regional authorities for the joint analysis of risk situations induced by slope instability considered as national priorities. The product can be also used for a better definition of the civil protection plans at inter-municipal level. The knowledge of past ground movements using quantitative measurements over wide areas represents a fundamental benefit for our activity. In particular, the added value of using PSI in the estimation of the state of activity of landslides based on a pretty good temporal interval (15 years) is impressive (no other techniques can provide an instrumental and objective measurements over a so large number of points and over wide regions).

48 User s feedback What decision making process could it help? How much could you save by using Terrafirma products? A better identification of the boundaries of unstable areas, especially in urban sectors of the slope, and of their state of activity improves the quality of the emergency plans. In order to obtain over basin and regional scale areas, ground displacement measurements, we should install a few thousands inclinometric tubes or geodetic benchmarks, with high costs in the installation and in the following measurement acquisition.

49 Conclusions Results confirm the capabilities of multi-interferometric InSAR data, integrated with conventional techniques and field surveys, to support landslide investigation at regional and slope scale. Considering the damages related to the landslide activity and the difficulties in the detection of the active, slow and dormant part of the landslide, especially over urban areas, the use of an InSAR approach can positively impact on the current hazard mitigation activities along national and local authorities. A next step is to tailor the service to new EO missions (Sentinel 1, Terrasar-X, CosmoSky Med).

50 THANK YOU FOR THE ATTENTION