project CIRAC - flood risk and vulnerability mapping in climate change scenarios

Pedro Seixas Vale
Chairman of APS (2008-2016)

The Portuguese Association of Insurers (APS) and the Foundation of the Faculty of Science, University of Lisbon (FFCUL) developed a project that we consider of undeniable interest to the Portuguese society called Maps of Floods and Risk in Climate Change Scenarios (CIRAC).

It is our belief that CIRAC will be the source of reference information for the flood risk analysis in mainland Portugal. It should be noted that currently there is a scientific consensus that climate change caused by the intensification of the greenhouse effect caused by some human activities will intensify throughout the XXI century. We know, therefore, that we will have to take measures for adaptation and mitigation to minimize the adverse effects of climate change and prevent the aggravation of their consequences for the population and the economy.

For the insurance industry, the CIRAC project is a tool to assess hazards that potentially will be held, which justifies its investment in the project, but it is also a contribution to the Portuguese society.

We intend that CIRAC will be widely divulged among insurers, reinsurers, scientific community, public entities and civil society sectors that demonstrate a recognized interest in the matter. The European Union, the Directive 2007/60/EC of 23rd October 2007, transposed into Portuguese law by Decree-Law 115/2010, of 22nd October, establishes a framework for the assessment and management of flood risks that Member States should follow, providing relevance to the need for the "... creation of flood hazard maps and flood risk charts indicative of potential adverse consequences associated with different flood scenarios ...".

In Portugal, where until now there was no information in a structured and detailed manner, floods are responsible for huge losses, and significant changes are still expected in precipitation regimes, the frequency and intensity of weather phenomenon and extreme climate events, such as intense rainfall over short periods.

Portugal, due to its characteristics, is very exposed to floods and there is no doubt that our territory will suffer significant damage caused by this risk. Over the past 40 years, there was a decreasing trend of rainfall and increased variability of accumulated rainfall in winter, with higher frequency of dry winters and rainy winters. The regionalized climate scenarios for Portugal, obtained through climate models, indicate the trend of increasing number of days with daily accumulated rainfall exceeding 50 mm in the north of the country until 2100.

The sea level rise, resulting from climate change, also contributes to a significant increase in the frequency and intensity of floods of marine origin. Due to the enormous complexity of the phenomena involved, opinions are divided with regard to the rhythms of the evolution of average sea level and respective magnitude. But there is no lack of consensus in the scientific community that the average sea level will continue to rise in the XXI century, which will affect the Portuguese territory with special intensity given its extensive coastline.

CIRAC allows the assessment of risk by providing benchmark indices that allow different types of vulnerability that assist the stakeholders in making strategic decisions. The study area for this project was divided into two scales: a macro-scale, where were identified flood areas, with the possibility of analysis up to the parish or postcode and a micro-scale for regions considered vulnerable based on the criteria of probability of flooding and flood risk, defining the latter as the combination of the probability of flooding with the potential adverse consequences to human health, the environment, economic activities and cultural heritage.

Given the high number of recorded cases of floods and torrents, the two urban centers, Lisbon and Porto were analyzed in greater detail, as well as Algés, Vila Nova de Gaia and Coimbra. With CIRAC, the insurance sector has a working tool of undeniable interest to society.

We hope that each of us learn how to use this tool in all its capacity so that together we can contribute to a better and more sustainable future for generations to come.