Model based projection of changes in low flow situations due to climate change in the federal state of Lower Saxony

摘要

This study aims to assess the potential development of low flow conditions up to the year 2100 in the catchment of Aller-Leine-Oker in Lower Saxony. To achieve this, a method for a more detailed representation of the soil water balance of meso-and macroscale hydrological impact models was elaborated, which leads to better simulation results especially regarding low flow conditions. Simulations based on the global climate model ECHAM5, the emission scenario A1B and the regional climate models Wettreg2006 and REMO show a significant decrease of low flow (NM7Q) for the near and far future (from about the 2030s). Other low flow indices also show strong tendencies towards drier conditions. Groundwater recharge and the near - surface soil water balance are also affected. Soil water availability and groundwater recharge are projected to significantly decrease on the basis of the applied scenarios.