Updated Flood Risk Index maps how a changing climate will shape flood risk in the future
- Published: Thursday, 21 July 2022 07:38
Marsh McLennan has released its updated Flood Risk Index 2.0, which shows how flood risks are expected to alter and develop as the climate changes.
Flooding is the most pervasive natural disaster, yet its costs are routinely underestimated. Climate change, economic and demographic trends, and a chronic shortfall in investment in resilience are combining to drive risk higher, says Marsh McLennan.
The Flood Risk Index includes risk scores for 180 countries in present-day conditions and in 1.5 °C, 2°C and 3.5 °C warming scenarios. The Index shows that a 3.5 °C warming would lead to a dramatic increase in flood risk globally, and that even limiting temperature rise to 1.5 or 2°C would substantially worsen the threat of flooding.
According to the Index:
- In Australia, 30 percent of the population and 28 percent of economic assets are at risk in present-day conditions, with a 2°C warming expected to increase these percentages to 49 percent and 52 percent, respectively.
- In Germany, 6 percent of the population and 6 percent of economic assets are currently at risk, while in a 2°C scenario, 16 percent of people and 17 percent of assets would be threatened by flooding.
- In the US, 11 percent of the population and 11 percent economic assets are currently exposed to flooding. In a 2°C scenario, these percentages will increase to 24 percent and 27 percent, respectively.
- In a 2°C warming scenario, India will be the G20 country facing the highest level of flood hazard, and South Korea will have the largest share of its population and economic assets exposed to flooding.
Given the propensity for large infrastructure projects to be situated near bodies of water, the Index now includes information about the global distribution of these critical assets. According to Marsh McLennan’s estimates, 23 percent of the world’s power generation capacity, 26 percent of international port outflows, and 18 percent of international airport seats are currently at risk of flooding. A 2°C warming would cause these percentages to rise to 41 percent, 52 percent, and 37 percent, respectively.