AZORIS: AN INFRASTRUCTURE TO IMPROVE SCIENTIFIC RESPONSIVENESS TO NATURAL DISASTERS IN THE AZORES

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1 AZORIS: AN INFRASTRUCTURE TO IMPROVE SCIENTIFIC RESPONSIVENESS TO NATURAL DISASTERS IN THE AZORES C. Goulart a, *, J. L. Gaspar a, G. Queiroz a a Centro de Vulcanologia e Avaliação de Riscos Geológicos, Universidade dos Açores. Rua da Mãe de Deus, Complexo Científico 3º Piso Ala Sul, Ponta Delgada, Açores, Portugal - catarina.ig.pereira@azores.gov.pt KEY WORDS: Geodatabases, GIS, SDI, Multi-risk, Azores, Natural Hazards ABSTRACT: The unique geotectonic and climatic setting of the Azores archipelago is the main reason for recurring geological events that take place over its territory. As witnessed and reported, since its settlement in the 15th century, Azores region has been the setting for landslides, earthquakes and volcanic eruptions, resulting from simple damages to loss of thousands of lives. Aiming to improve the responsiveness to re-occurring events, as well as the day-to-day research on multi-risks, at Centro de Vulcanologia e Avaliação de Riscos Geológicos (CVARG), a great effort has been made since 2002 to create a GIS-based structure (AZORIS) that could store and manage all information available for risk analysis and provide access to data for the interested community. ESRI technology is being used and the data structure has been adapted, to optimise space requirements and processing capabilities. The current data model was established taking into account the thematic, typological and geographic distribution of the information. Due to the spatial complexity of the Azores archipelago, datasets were defined for each of the islands, as well as for the archipelago as a whole, in order to enclose data outside the spatial extent of the islands. Metadata has been mandatory since the beginning of the information compilation process; nevertheless, with the INSPIRE directive being applied, further analysis is being required to fulfil the guidelines now defined. The present work discusses the data model structure applied, while considering the definition of the parameters for data storage and compilation. 1. INRODUCTION The Azores archipelago is located in the area where the American, Eurasian and Nubian lithospheric plates meet, forming the Azores triple junction, which makes this an important volcanic and seismic zone of the North Atlantic. Since its settlement, the Azores has been affected by several earthquakes, volcanic eruptions and landslides, causing thousands of deaths and severe social and economic impacts (Gaspar et al., 2011). Making an operable GIS-based platform that joins data for geological hazards assessment, under standardized parameters, will facilitate an easier analysis of these hazards individually and also organize the combined results in a visually-friendly environment. It will be faster to evaluate geological hazards and provide tools for the authorities to improve decisions on land use policies, regional planning and minimize the impacts of future natural disasters on the local populations. Quicker spatial analysis results will also be critical in emergency planning, in order to respond to civil protection information requirements during hazardous events or simulations exercises. A key to improve scientific responsiveness to natural disasters is to provide research with quality data. Spatial analysis using GIS tools can be very valuable, but they demand valid layers of information with spatial conformity. Azores cartography is produced by means of both a geographic coordinate system or UTM projections, that includes local or global datum. Moreover, as the Azores archipelago is formed by nine volcanic islands distributed over more than 600 km of the North Atlantic Ocean, in a SE-NW direction, it comprises two UTM zones, 25S and 26S (Figure 1). The Instituto Geográfico do Exército (IGeoE) published a 1:25000 vector base cartography for the territory in 2000, providing a uniform base cartography for the whole archipelago. With IGeoE cartography, the Centro de Vulcanologia e Avaliação de Riscos Geológicos (CVARG) acquired a homogeneous topography for all the islands that serve as a base for developing its own thematic layers of information. * Correspondence to: Catarina Goulart, Centro de Vulcanologia e Avaliação de Riscos Geológicos, Universidade dos Açores, Rua da Mãe de Deus, Complexo Científico 3º Piso Ala Sul, Ponta Delgada, Açores, Portugal. catarina.ig.pereira@azores.gov.pt.

2 Figure 1. Azores archipelago location Until 2000, most topographic and geological hazards maps were inconsistent and required adaptation to current base cartography. The inconformity of data resided, not only in the difference in coordinate systems used, but also in morphological changes on the islands over time due to natural and/or human impact (Goulart, 2004), making it impossible to transform some maps. In order to overcome this problem, AZORIS was conceived as a structure to organize and normalize all data that could eventually be used in the assessment of natural hazards, in addition to the collection of existing information. 2. GEODATABASES STRUCTURE AND DATASETS 2.1 Data Structure in 2003 In 2002 (Gaspar et al., 2004), CVARG began the process of creating a database structure for geological risks analysis in the Azores (AZORIS) with an architecture based on ESRI Technology. The scope was to produce a single geodatabase that would gather all information available at CVARG. At that stage, the information was grouped according to geographic extension and subject (Figure 2). The next step of this process was to convert the IGeoE original base cartography into ESRI Shapefile format, in order to standardize the data structure. This included the aggregation, subdivision, addition, elimination and editing of attributes and features into more efficient groups of layers. Specific data themes on volcanology and geology were later defined and a common structure developed that would allow for future data collection. Figure 2. AZORIS data structure in 2003 (Gaspar et al., 2004) 2.2 Geodatabase structure in 2007 In 2007, a joint effort with ESRI Portugal, to transpose the existing data into a SDE geodatabase structure, revealed that the geodatabase architecture would have to be more complex in order to improve data management. Four SDE Geodatabases were created: 1) CARTO_CVARG; 2) AZORIS; 3) MONITORING and 4) GIST and three were replicated from the Cartography Department of the Regional Government of the Azores (GRA): 1) ORTOFOTOS 2) CARTORASTER and 3) CARTOVECTORIAL (figure 3).

3 Table 4. Enclosed information in the 2007 SDE geodatabases The CVARG SDE geodatabase datasets were defined according to geographic and/or administrative boundaries, and for each of the coordinate systems of existing data (Table 5). Even though the IGeoE cartography in UTM WGS84 was defined as the official base cartography, datasets in the geographic coordinate system and UTM local datum were created to store data and layers that could not be transformed to the new bases. Figure 3. AZORIS geodatabases structure in 2007 GCSWGS84 WGS84UTM25 WGS84UTM26 OM39UTM25 BSWUTM26 SBUTM26 COORDINATE SYSTEM Geographical Coordinate System WGS84 Geographical Coordinate System WGS84 - UTM Zone 25N Geographical Coordinate System WGS84 - UTM Zone 26N Observatorio Meteorologico 1939 UTM Zone 25N Graciosa Base SW 1948 UTM Zone 26N Sao Braz UTM Zone 26N The GRA SDE geodatabases ORTOFOTOS, CARTORASTER and CARTOVECTORIAL gathered the orthophotographic imagery, vector base cartography and raster base cartography respectively, for the Azores archipelago (Table 4). Those three SDE geodatabases were a mirror of the existing geodatabases in the cartography department of the GRA. CVARG researchers access to the databases was restricted to purposes outlined in existing protocols with Azores Regional Government and limited to read-only access. The structure of the CVARG SDE geodatabases was defined taking into account the information that would be stored (Table 4). CARTO_CVARG SDE geodatabase stored the vector base cartography created or compiled by CVARG, such as topography and administrative boundaries. AZORIS SDE geodatabase established the structure to collect specific thematic data, produced or compiled by CVARG on: gases geochemistry; geodesy; geology; geophysics; hazards; hydrogeology; landslides; meteorology; petrology; volcanology; vulnerabilities and related subjects. The MONITORING SDE geodatabase was prepared to collect the information coming from the geophysical, geochemical, geodetic and meteorological monitoring systems owned or controlled by CVARG. The SDE geodatabase GIST was created as a workspace for ongoing GIS tasks, before they were integrated into other SDE geodatabases. SDE GEODATABASE CARTO_CVARG AZORIS MONITORING ENCLOSED INFORMATION Base cartography compiled by CVARG or edited from CARTORASTER and CARTOVECTORIAL CVARG produced cartography on volcanology and geological risks related subjects Data from the CVARG monitoring systems CVARG temporary data workspace GRA Ortophotos GRA Raster format cartography GIST ORTOFOTOS CARTORASTER CARTOVECTORIAL GRA Vector format cartography Table 5. List of acronyms for the coordinate systems used SDE geodatabase structure does not permit subdivision and grouping of data. Feature class and table names were simplified to minimize their length and to facilitate quick understanding of their contents. This included a series of acronyms that defined: the spatial extent (Table 6), the subject (Table 7) and the feature/table name. AZO GRA SJO FLO COR BDJC FORM SPATIAL EXTENT Azores archipelago Graciosa Island São Jorge Island Flores Island Corvo Island Dom João de Castro Bank Formigas Islets Table 6. Examples of spatial extent acronyms GEOG GEOL HAZAR LANDS VOLC VULN SUBJECT Geography Geology Hazard Landslides Volcanology Vulnerability Table 7. Examples of subject acronyms Further specifications on data structure were established for the AZORIS SDE geodatabase as it stores the information compiled by CVARG researchers. The data model structure for the AZORIS SDE geodatabase comprises a series of datasets, feature classes and tables. Feature classes and tables have a defined data structure that includes field name, type and length for each feature class or table (Figure 8). To avoid orthographic errors and enforce data

4 integrity, domains were created to facilitate data-entry of attributes (Figure 9). Figure 8. Example of an AZORIS feature class field definition Figure 9. Example of an AZORIS domain This data structure was imported into the geodatabases, the coordinate systems were assigned to each dataset and then the data was loaded. The GIS team advanced with the CARTO_CVARG SDE geodatabase data-loading process, as most of the contents were already normalized according to the defined rules. 2.3 Geodatabase structure in 2010 The evolution of communication technologies and new versions of the software justified the reassessment of AZORIS. At the end of 2010, when preparing data for internal publication, further changes were made to the structure, in order to improve storage of raster files and the management of published data. The current structure is composed by six SDE geodatabases: 1) INSPIRE; 2) CARTO_CVARG; 3) AZORIS; 4) MONITORING; 5) SIGWEB and 6) GIST and two folders of file geodatabases: 1) CIGAM, for raster data from the government and other entities; and 2) FileGeoDB, for CVARG raster data (Figure 10). Figure 10. AZORIS geodatabases structure in 2010 The main changes were the exclusion of raster SDE geodatabases (ORTOFOTOS and CARTORASTER), as they were converted to file geodatabases for better performance, and the implementation of the INSPIRE and SIGWEB SDE geodatabases. The INSPIRE SDE geodatabase replaced the former CARTOVECTORIAL SDE geodatabase compiling vector information from other institutions, normalized under the INSPIRE Directive (2007/2/EC). SIGWEB SDE geodatabase was created to facilitate publishing data, as it contains only replicas of data existing in CARTO_CVARG and AZORIS SDE geodatabases (Table 11). SDE GEODATABASE CARTO_CVARG AZORIS MONITORING GIST SIGWEB INSPIRE ENCLOSED INFORMATION Base cartography compiled by CVARG or edited from CARTORASTER and CARTOVECTORIAL CVARG produced cartography on volcanology and geological risks related subjects Data from the CVARG monitoring systems CVARG temporary data workspace CARTO_CVARG and AZORIS data for publication Cartography from other institutions, normalised under the INSPIRE Directive

5 Table 11. Enclosed information in the 2010 SDE geodatabases With this new approach and the growing need to have data available for publication, concerted effort is being made to compile existing information. The structure has been defined in order to ensure easy maintenance, use and management. 2.4 Metadata Metadata is crucial to guarantee the quality of data in use, since it provides additional information necessary for adequate decision-making. Metadata supplies information on the author, period, scale and scope in order to differentiate between several thematic layers. Finding more than one version of the same theme can be problematic, especially if no description is provided to the user. Compiling information from different authors, in different formats, without metadata to assist interpretation is a difficult task. Moreover, the lack of complete information has demanded the re-construction of some thematic cartography. If collecting suitable hazard data for the region is complex, then tracking the technological evolution on processing and publishing data has been one of the great challenges. The INSPIRE Directive implementing guidelines that specify the structural provisions for geological data themes (Annex II) has not yet been published. To date, the CVARG approach has been proactive and comprehensive in providing metadata for each theme. This has included, not only basic information, but more importantly: 1) field attribute definitions and 2) processing steps (especially with analysis results). Therefore, taking into account the specifications already available from the Annex I themes, CVARG is fulfilling all the mandatory specifications. The concern remains that relevant metadata will be lost in the process of converting to the INSPIRE format, and that potential users will have limited information (such as losing track of the processes used to derive final published works). Regardless, CVARG continues to utilize the ESRI ArcCatalog Metadata Editor both to visualize and manage metadata content. This allows the visualization of all documentation by CVARG users and supports field attribute and process information, and not just obligatory fields required by the INSPIRE Directive. References from Journals: Gaspar, J.L., Goulart, C., Queiroz, G., Silveira, D., Gomes, A. (2004) - Dynamic structure and data sets of a GIS database for geological risk analysis in the Azores volcanic islands. Natural Hazards and Earth System Sciences, 4, p References from Other Literature: Goulart, C. (2004) Aplicação de sistemas de informação geográfica à análise de riscos geológicos. Tese de Mestrado em Vulcanologia e Avaliação de Riscos Geológicos, Departamento de Geociências, Universidade dos Açores, 119p. References from websites: EC. ( ) INSPIRE Directive and Data Models, Last visited 15/04/2011, Available at: (Last accessed 15 Apr. 2011). Gaspar, J.L., Queiroz, G., Ferreira, T., Amararl, P.,Viveiros, F., Marques, R., Silva, C., Wallenstein, N., Geological Hazards and Monitoring at the Azores (Portugal). (Last accessed 15 Apr. 2011). 2.7 Acknowledgements and Appendix (optional) Catarina Goulart is supported by a Ph.D. grant from Fundo Regional da Ciência e Tecnologia, Região Autónoma dos Açores. The authors would like to thank José Medeiros for data compilation and Ruben Furtado for english and contents reviewing. This work is supported by the Pluriannual Funding Programme of Fundação para a Ciência e a Tecnologia to CVARG and Azores Geological Risk Mapping project supported by the Regional Government of the Azores. 2.5 Conclusions Setting an infrastructure to store and manage all information available for risk analysis and provide access to data, for specific users, will develop scientific responsiveness to natural disasters. Creating such an infrastructure requires hardware, software and liveware capabilities that can store, process and maintain the system. To be effective, AZORIS must provide researchers with quality data that is regularly updated and spatially consistent in order to improve risk analysis in the Azores. 2.6 References and/or Selected Bibliography