Will measuring losses to natural disasters really tell us about changes in risk?
Two years ago, in March 2015, representatives of 187 countries met in Sendai, Japan to agree to the Sendai Framework for Disaster Risk Reduction for the period 2015 to 2030. Last month, on February 2nd, the UN General Assembly approved seven global targets to reduce risk from natural disasters, and agreed to a set of indicators for measuring global progress toward these targets.
The indicators for Targets A, B, and C aim to reduce by 2030 mortality, affected people, and economic loss, respectively. The targets will be to reduce impacts in a relative sense, so that mortality and affected people will be measured per 100,000 population; and economic loss will be measured in relation to gross domestic product. Global Target D aims to reduce risk to critical infrastructure, including health and educational facilities. In the article “How can the world reduce losses for the poor?”
Robert Glasser, UNISDR, states that the measurement of the indicators introduces a “major degree of accountability” for the seven global targets, but will the proposed measurement of disaster losses actually be useful for monitoring changes in risk? The answer is yes and no. Why the Sendai indicators are not enoughWhile measuring these indicators will be quite useful, it is highly unlikely that this monitoring process alone will allow the world to accurately measure the actual reduction in risk, particularly for rare, high impact events, such as major earthquakes, cyclones and volcanic eruptions. For instance, Munich Re estimates that worldwide the average annual deaths for the past ten years from all natural disasters was about 60,000 people, while last year accounted for only 8,600 deaths.
Yet, in the 2004 Indian Ocean Earthquake and Tsunami, more than 230,000 people died in a single event. With such a high variation in annual losses at the global scale, there is little chance that monitoring such variation alone will give us an accurate picture of risk at a global scale, and certainly not at a national or urban scale. An alternative way of more accurately measuring riskBy the end of 2018, GEM will have produced a global earthquake risk model, which will provide a baseline at national level for earthquake hazard and risk globally. Moreover, the model and all of the tools and data underlying the model will be available openly, freely and transparently for the public good. This information can and should be used to monitor risk.
Since risk is a function of hazard, vulnerability and exposure, the trends in these variables measured over time will allow us to determine the extent to which we are meeting the global targets for risk reduction. Moreover, this will be possible not only at the global level, but also at the national and even urban/local levels. Changes in exposure will be necessary to determine how the distribution of population, assets and investments are evolving spatially and temporally. Similarly, measuring vulnerability will be critical to understand how social, physical and economic factors are evolving and contributing to changing risk. Changes in the physical risk to schools, hospitals and other vulnerable building types can be estimated at local to global levels by collecting exposure and vulnerability information and tracking retrofits and new construction over time.
One approach would be to collect information on the ratios of numbers of buildings constructed above and below building code standards, such as for unreinforced masonry, the building class most vulnerable to earthquake damage and casualties. Trends could be tracked to estimate changes in risk in terms of potential physical and economic loss. Finally, disaster mitigation could be incentivized by providing tools to demonstrate the cost-benefits of retrofitting or replacing these and other vulnerable buildings in high-risk areas. Thus, the information in risk models can be used to both track changes in risk as well as to identify cost-effective opportunities for risk mitigation and reduction activities.
GEM’s contribution to disaster risk reductionGEM is very well placed to assist in the process of informing the recently agreed Sendai targets by working with countries to develop national earthquake hazard models, by assisting in collecting and analyzing vulnerability and exposure data, and by combining this information into a risk modeling and monitoring framework at national and urban levels. This would be accomplished by further developing partnerships in developing countries to increase their capacity to assess and manage earthquake risks.
GEM is also developing tools that can be used in both developing and developed countries to assess the costs and benefits of mitigating and/or reducing these risks. With continued investment over time, these and other risk models, tools and data can be further developed to provide much needed support to achieving the goals of the Sendai Framework.