Downscaling scenarios to the delta
Global scenarios may not fit the specific context of countries, regions or deltas. The Water, Climate, and Future Deltas hub therefore developed regional delta scenarios that account for local and delta-specific context.
Regional delta scenarios
Global projections, e.g. of land use or urban development may not be valid for deltas, for example where the natural environment of deltas does not support projected land-use types. Moreover, local feedbacks between projected changes and environmental conditions in the delta may occur, such as land subsidence resulting from groundwater extraction. The resulting subsidence might then render an area unsuitable for a land-use type predicted by a global projection. Researchers at the hub therefore developed regional delta scenarios that are consistent with the global SSP and RCP scenarios, but account for local and delta-specific context. We demonstrate this in videos for three deltas: the Rhine-Meuse delta, the Mekong delta and the Ganges-Brahmaputra-Meghna delta.
The heavily engineered Rhine-Meuse delta is projected to experience low sediment supply and an increasing sediment loss due to dredging which enhances its vulnerability to flooding and increases the need to explore potential adaptation measures.
More storylines about the Rhine-Meuse delta
The rapidly urbanising Mekong delta is experiencing land subsidence which increases its vulnerability to flooding and requires mitigation measures that reduce groundwater extraction.
The densely populated Ganges-Brahmaputra-Meghna delta is facing multiple climate-related and social challenges, requiring long-term strategies for adaptive management.