South America incorporates some of the most seismically active regions on the planet, where the South American subduction zone generates the forces to create the Andes Mountains and drives the occurrence of destructive earthquakes across Chile, western Argentina, Bolivia, Ecuador, Peru, Colombia and Venezuela.
In turn, the high vulnerability of many structures and the high population density of the main cities are factors that contribute to the region’s high seismic risk. In the last two decades alone, over 3,000 fatalities have been reported, and the economic losses have exceeded 30 billion USD (EM-DAT, www.emdat.be).
While expert capabilities exist in these countries to assess earthquake risk, the information, infrastructure, tools, and collaboration networks necessary to develop comprehensive knowledge among scientists and engineers and to move this knowledge into the mainstream of disaster risk reduction activities has been lacking.
The approach is to bring together international best practice tools and methodologies with local expertise and knowledge needed to establish local ownership and define risk assessment objectives and priorities. GEM Foundation combined these elements and focused on developing local capacities across sectors (academic, public and private), across technical disciplines (e.g., hazard, risk, IT), and through the implementation of disaster risk reduction policies and programs.
The program of capacity development was initiated in 2013 with the South America Risk Assessment (SARA) Project to bring experts, institutions, and stakeholders from 7 countries to develop a regional assessment of earthquake hazard and risk. GEM provided its OpenQuake earthquake hazard and risk analysis software and other tools and databases freely and openly to all participants. More than 50 of the region’s experts across 17 institutions collaborated to produce critical data sets, develop common approaches, and develop open-source tools for both data collection and interpretation.
The SARA Project, completed in December 2015, provided the foundation for formal and informal collaborations at many levels and for many purposes. GEM subsequently developed formal partnerships across public and private sectors (e.g., SuraAmerica Insurance, the Geological Survey of Colombia, EcoPetrol), academic partnerships (e.g., EAFIT Univ, Univ del Norte, Univ Catolica Chile), non-profits (e.g., OSSO), and most recently, with municipal governments (Cali, Colombia and Quito, Ecuador), for urban risk assessments. (complete list)
Andean Region (Venezuela, Colombia, Ecuador, Peru, Bolivia, Chile and Argentina)
The project was carried out by experts and institutions from the region using to the extent possible open data sets, methodologies and tools such as GEM’s new open source software, the OpenQuake Engine and other OpenQuake tools.
The project revolved around 5 modules: hazard, exposure and physical vulnerability, socio-economic vulnerability and resilience, loss estimates and city scenarios. The modules were carried out by a variety of experts/scientists from the region, in collaboration with the project coordinators and, where relevant, the GEM Secretariat.
1. Seismic hazard
In early 2013 the Global Earthquake Model (GEM) published seven Requests for Proposal covering topics related to the compilation of basic datasets as well as the creation and calculation of an updated probabilistic seismic hazard input model for South America. Five consortia of South American researchers responded to this request and submitted proposals, which were reviewed in an initial stage by scientists working at the GEM Secretariat, and successively discussed in a meeting in Bogota held in December 2013 at the “Servicio Geologico Colombiano”.
2. Exposure and Physical Vulnerability
Development of exposure datasets and vulnerability functions for South America at regional, national and/or sub-national levels have been considered. Modelling of exposure and physical vulnerability in the most earthquake prone countries is the main goal in the first stage of the project.
3. Social Vulnerability and Resilience
The social vulnerability component of SARA comprises the development of composite indicators of social vulnerability and resilience along with their robustness testing and validation. The objective is to provide tools and information useful for understanding the potential effects of earthquakes in communities of South America.
4. National and subnational estimation of losses
An open and transparent seismic risk assessment for the Andean countries has been performed. A probabilistic approach was followed for the calculation of risk metrics, that includes average annual economic and human loss maps, mean loss exceedance curves per country, and statistics that reveal which building classes are most vulnerable to earthquakes.
5. City Scenarios
Following the objectives of SARA, the development of city scenarios is crucial for planning risk management strategies in cities with larger concentration of population and exposed to significant hazard. In this sense, the GEM Secretariat has been seeking collaborations with research groups and governmental stakeholders that will be the end users of case studies in Lima (Peru), Quito (Ecuador), Medellín (Colombia), Iquique, Osorno and Rancagua (Chile).
Capacity development and institutional strengthening
To promote sustainability, SARA’s work included the following: capacity development and institutional strengthening, and stakeholder engagement. The outcomes of activities in these areas are described below.