Methodology

This dashboard is based on a large ensemble of future global projections of six mobility-related climate hazards: heat waves, droughts, wildfires, river floods, tropical cyclones, and crop failures (Lange et al., 2020). These projections are available from a number of climate impact models, which each simulate certain weather-related physical processes, for different points in the future and for alternative climate scenarios (RCPs) that depend on factors including future greenhouse gas emissions. For each point in time and each climate scenario, the data shown here represent the median average across all available model simulations, to use as robust an estimate as possible.

In addition to showing the extent to which different geographical areas of the world are affected, the dashboard visualises when and where humans will likely be exposed to the six climate hazards. This was done by overlaying the hazard projections with projections of future population distributions (Jones & O’Neill, 2016), which are available for alternative socio-economic scenarios (SSPs) that depend on factors including population growth rates and economic developments.

To identify areas in which particularly vulnerable populations are exposed to hazards, the above data were overlaid with future global projections of economic income, measured in gross domestic income per capita (Wang & Sun, 2022). Vulnerable populations were then defined as those living in the 10% lowest income areas worldwide.

To place the future hazard projections in the context of past human mobility driven by droughts, wildfires, floods, and storms, the dashboard provides outlines of the geographical areas where internal displacements due to these hazards have been most severe (IDMC, 2023).

The dashboard provides map visualisations of where areas and populations are expected to be exposed to hazards. In addition, it provides aggregate analyses showing how the number of affected people across selected geographical areas is projected to change across time as well as under different climate and socio-economic scenarios.

Caveat: It is important to note that the models underlying the data shown here are simplifications of a complex reality and as such are subject to uncertainties. As understanding of the climate system evolves and models continue to improve, projections need to be interpreted with awareness of the dynamic nature of scientific modelling.