EO Information Services in support of Satellite Tools for Building Flood Defence Systems in Guyana

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1 EO Information Services in support of Satellite Tools for Building Flood Defence Systems in Guyana F. N. Koudogbo and A. Arnaud Altamira Information J. Leen, Eurosense World Bank HQ, Washington DC Date : 12 April 2011

2 Introduction : The EO Service Providers Altamira Information ALTAMIRA INFORMATION is an experienced Earth Observation company that provides ground deformation measurements with millimetric precision and mapping solutions using satellite images. ALTAMIRA was founded in Barcelona in 1999 and opened offices in Toulouse (France) and Calgary (Canada) part of the CLS group since 2010 The team brings together more than 25 staff with wide InSAR technical and scientific background. ALTAMIRA services are provided using its own PSInSAR software: the Stable Point Network processing chain (SPN). Main clients in the domain of infrastructures, mining and Oil and Gas Activities in institutional framework for disaster managements Since 2009, ALTAMIRA has been the Coordinator of the European Space Agency s GSE Terrafirma project. Terrafirma Project Organisation

3 Introduction : The EO Service Providers EUROSENSE EUROSENSE offers high quality geographical information (from spaceborne, airborne and seaborne data). All products meet high standards for quality, precision and reliability. Established in 1964, with its headquarters in Belgium and offices in many European countries About 200 specialized staff members (engineers, geographers, topographers, hard- and software specialists) Remote sensing applications: Land use/land cover mapping, Flood risk monitoring, Environmental monitoring, Height modelling, Thermography, Main types of clients: International (EC, FAO, WB, UN,...), national and regional governments, cities and municipalities, public and private service corporations, consultancy firms and software providers EUROSENSE is an active player in geoinformation services in the whole world for about 50 years.

4 Background : The World Bank Project Project users : World Bank Project context : World Bank is currently preparing the Conservancy Adaptation Project (CAP) Its objective is to reduce the vulnerability of catastrophic flooding in Guyana's low-lying coastal area that is currently threatened by sea level rise resulting from global climate change. Project Information requirements VHR SAR based interferometric terrain deformation mapping, Urban mapping of infrastructure & buildings, High Resolution DEM, Flood risk assessment, Accurate estimation of the effective rate of sea level rise. Reason / Driver for this information Estimation of possible subsidence phenomena in the coastal lowland and to study the flood defense system based on an old dyke system

5 The EO Information Products : Service 1 Information provided VHR SAR based interferometric terrain deformation mapping Analysis of terrain deformation based on the processing of radar satellite data with the SPN (Stable Point Network) interferometric software (certified by DLR). Developed by Altamira Information, SPN is capable to extract precise displacement and position information of the radar stable points. Velocity expressed in mm/yr for each measurement point Time series of the displacement on the monitoring period InSAR study based on VHR TerraSAR-X satellite data - optimal to achieve high density measurements in specific constructed areas. In order to overcome the problem of temporal decorrelation (due to presence of vegetation), installation of 15 Corner Reflectors (man-made reflectors anchored to or near the structure to be monitored e.g. the flood defense system)

6 The EO Information Products : Service 1 Information provided Technical Specifications AOI is the coastal lowland of Guyana, including the City of Georgetown. Geometric accuracy TerraSAR-X 1/10 th pixel TerraSAR-X frame Spatial resolution Pixel spatial resolution Absolute location accuracy Relative X, Y accuracy Thematic accuracy Better than 3 m Better than 2 m (GPS precision for CRs) Metric in both E-W and N-S direction (GPS precision for CRs) 2 mm/yr Technical specifications of the displacement for each measurement point

7 The EO Information Products : Service 2 Information provided Urban mapping of infrastructure & buildings Source data Format Scale / MMU Area produced VHR GeoEye-1 satellite imagery + ancillary data (topographic map...) GIS compatible vector / raster format (as required) 1: / 0,25 0,5 ha 300 km² Reference date Accuracy Legend Parameters Thematic: > 80 %, geometric: < 1m can be adapted to User requirements Requested construction parameters per street block TBD (average building height, average building density...) Urban atlas product is developed and qualified in GMES projects (GSE Land, GMES Global Urban Services, geoland). The product is audited and approved by an external audit company Artificial surfaces Urban fabric Continuous urban fabric Very dense urban fabric (S.L.>80%) Discontinous urban fabric Dense urban fabric (S.L.:50% - 80%) Medium density urban fabric (S.L.: 30% - 50%) Low density urban fabric (S.L.: 10% - 30%) Special urban fabric features Apartment blocks with communal open space Isolated structures Industrial, commercial and transport units Industrial, commercial, public and private units Industrial areas Commercial areas Public, military and private services Water supply infrastructure, sea walls and flood defences Road and rail networks and associated land Fast transit roads and associated land Other roads and associated land Railways and associated land Port areas Airports Mine, dump and construction site Mineral extraction & dump site Dump sites Construction sites Urban Mapping of the City of Concepciòn (Chile) Land without current use Artificial non-agricultural vegetated area (scale 1/10.000) Green urban areas Sport and leisure facilities Agricultural areas Forest and semi-natural areas Wetlands Water

8 The EO Information Products : Additional Desirable Information 1 High resolution DEM based on VHR SAR data Due to the presence of clouds in optical data for the area of interest, VHR radar solution is suitable for DEM generation. Digital Elevation Model (DEM) generated using 11-day interferometric pairs Reduction of impact of temporal decorrelation. Better estimation of the atmospheric artefacts Tunisia HR DEM generated with High Resolution SpotLignt TerraSAR-X data (4x4m) Vertical accuracy (m) 5 TerraSAR-X Corresponding SRTM DEM with 90m pixel Spatial resolution (m) 9 Coverage (km x km) 30 x 30

9 The EO Information Products : Additional Desirable Information 2 & 3 Flood Risk Simulation - Mapping of the stability of the flood defense system Simulation of a flooding - Flood extent and water depth - Resolution: approximately 9m - Input data: EO and DEM from Coverage: around 300km² - Thematic accuracy: depended on input data flood simulation, DEM, urban map and other available data, - Geometric accuracy: depends on DEM Information on the sea level rise based on terrain subsidence measurement. Accuracy depends on: Accurate estimation of the effective rate of sea level rise for flood defense Subsidence measurements Urban mapping product A priori information provided by WB (historical measurement of sea levels... ) Flood risk portfolio developed and qualified in GMES projects (Risk-EOS and SAFER) Sea level rise rate +A mm/year Effective rate of sea level rise A+B mm/year Ground subsidence rate Bmm/year Illustration of the effective rate of sea level rise estimation

10 The EO Information Products : What Service 1 brings Pros/Cons Benefits / Advantages Remote sensing method independent in-situ measurements large coverage Extensive number of measurement points (in space) compared to other methods. Access to the large archive of SAR images (over 20 years) Analysis of historical motion Millimetric precision of the measurement in z direction (while more imprecise with GPS) Limitations / Constraints No a priori information on the number of measurement points, neither on their location Metric relative accuracy in X and Y direction for natural measurement points (while centimetric for GPS) Need for a reference point in a stable area for the computation of the displacement - all measurements are relative, need for GPS for absolute displacement Deformation maps and the DEM will allow identifying the affected zone, their extents and assessing the localization of infrastructures that have been damaged.

11 The EO Information Products : What Service 2 brings Pros/Cons Benefits / Advantages Up-to-date digital detailed urban reference layer Spatial view on the distribution of urban infrastructure Derivation of statistics (e.g. Quality of life indicators) Input for flood risk and damage assessment Decision support system for urban planning Easy to update Limitations / Constraints Thematic accuracy highly depended upon quality of available ancillary information. Geometric accuracy will depend upon available reference data All available ancillary data is needed (georeferenced digital or analogue data) to generate the product The urban map gives a spatial view on the distribution of urban infrastructure. It will be used as input data to assess potential flooding and in this way assess potential vulnerable areas.

12 Examples of Previous Use: HURRICANE KATRINA: before and after The project: Movement map before Katrina Movement map after Katrina Mapping subsidence and uplift in May 2002-Jun 2005 New Orleans before and after Sep 2005-Jan 2007 Hurricane Katrina in 2005 Partners: Canadian Space Agency (CSA) 1 Altamira Information United States Geological Survey (USGS) 1 0 [cm/year] National Aeronautics and Space Administration (NASA) 0 [cm/year] -1 Source: -1 Historical movement maps provide useful information for identifying vulnerable zones and building strategies for facing natural disasters

13 Examples of Previous Use: Urban Mapping in Concepción (Chile) Development of a set of urban land use / land cover products of Concepción (Chile) Project: Analysis of Geographic expansion for European EO Services: Latin America and the Caribbean (JAGUAR project) Urban Atlas Map EUROSENSE has been in charge of the generation of a detailed urban map of Concepción (+ change detection). The resulting map has been used for urban planning, and used as reference for assessing the February 2010 earthquake damages Testimony from the Users -On Urban Atlas: Igor Bacigaluppi Alvarez (Coordinador Sistema Información Territorial, Servicio de la Vivienda y Urbanización (SERVIU), Concepcón, Chile) Specifically I want to refer to the urban map as an extraordinary product that encouraged authorities and officials of the region to make the best decisions in an informed manner. This can now be done in relation to the protected natural area (Nonguen Reserve) and thus allows for better protection and conservation planning against unfriendly environmental measures. -On the use of the product as a reference layer alter the earthquake: The produced responded well to our requirements. After the earthquake, we could add local government information like the type of damage, people affects, photographic register, etc. to the product information layer. Change Detection

14 Thank you Questions & Discussion Date : 12 April 2011