Human and economic impacts of natural disasters: can we trust the global data?

Abstract

Reliable and complete data held in disaster databases are imperative to inform effective disaster preparedness and mitigation policies. Nonetheless, disaster databases are highly prone to missingness. In this article, we conduct a missing data diagnosis of the widely-cited, global disaster database, the Emergency Events Database (EM-DAT) to identify the extent and potential determinants of missing data within EM-DAT. In addition, through a review of prominent empirical literature, we contextualise how missing data within EM-DAT has been handled previously. A large proportion of missing data was identified for disasters attributed to natural hazards occurring between 1990 and 2020, particularly on the economic losses. The year the disaster occurred, income-classification of the affected country and disaster type were all significant predictors of missingness for key human and economic loss variables. Accordingly, data are unlikely to be missing completely at random. Advanced statistical methods to handle missing data are thus warranted when analysing disaster data to minimise the risk of biasing statistical inferences and to ensure global disaster data can be trusted.

Fig. 1

Missing data patterns and proportions of missing data for key human and economic loss variables in EM-DAT across all disaster events attributed to natural hazards and occurring between 1990 and 2020. Black shading denotes missing data for one or more disaster events; grey shading denotes observed data. Disaster events are ordered along the x-axis by the STATA default: from the least to the most missing across the variables analysed. The proportion of missing data for each variable, given as a percentage of the total data, is shown to the right-hand side of the figure. Variables are presented in descending order of missingness. Human loss variables include No. of Affected, defined as the number of people requiring immediate assistance during a period of emergency; No. of Missing, defined as the number of people whose whereabouts is unknown and who are presumed dead; No. of Deaths, defined as the number of people who lost their lives as a result of the disaster event; and Total Deaths, defined as the sum of No. of Affected and No. of Deaths. Economic loss variables include Reconstruction Costs, defined as the costs incurred due to the replacement of lost assets and the implementation of disaster mitigation measures; Insured Damages, defined as economic losses born by the insurance sector; and Total Estimated Damages, defined as a value of all economic losses directly or indirectly related to the disaster event.