Flooding of a warmer world: learning from the Last Interglacial

Summary

Global warming impacts the hydrological cycle and thus affects human livelihoods. Global precipitation patterns and their extremes are likely to undergo substantial shifts, as illustrated by General Circulation Models. General Circulation Models are run by increasing greenhouse gas forcing, whereas the other climate components are left to adjust dynamically; they thus refer to a future climate that we cannot validate. General Circulation Models outputs are then used in hydrological and impact models to simulate changes in riverine flood risk. An alternative strategy is to use simulations based on past climate states that could resemble the future. The Last Interglacial period (LIG; ~125,000 years ago) seems the most appropriate analog of possible climate at year 2100 and beyond, as compared to today: it was warmer; sea level was several meters higher; ice sheets smaller; monsoons were likely stronger; and, most importantly, proxies exist to validate LIG simulations.
Therefore, we use the output from existing runs of multiple LIG climate models, as input to global hydrological, hydrodynamic and impact models for river floods; the first such application to the best of our knowledge. We employ state-of-the-art large-scale models to reconstruct the shifts of geographic risk patterns. Notably, we contrast the LIG climatological datasets as well as the flood hazard results against existing proxies. We will thus deliver to the community and the public a validated picture of the flood impacts of a climate that might resemble the future.

Details

Project number

16712

Main applicant

Dr. P. Scussolini

Affiliated with

Vrije Universiteit Amsterdam, Faculteit der Aard- en Levenswetenschappen, Instituut voor Milieuvraagstukken (IVM)

Duration

12/01/2018 to 04/01/2019