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The annual average temperature in Lower Saxony rose by 1.5 degrees C since 1881, with maximum summer temperatures and the frequency of summer droughts increasing. At the same time, the length of the growing season has extended and annual mean precipitation amounts have risen by 17 % during the period between 1881 and 2011. While winter precipitation increased significantly, summer precipitation exhibited a downwards trend and low water indices for inland waters indicate a growing severity since 1960. Multi-model ensembles of a variety of climate studies suggest that the climate trends started in the past century will continue at least until 2050. The averaged change signal of the annual mean temperature is projected by different studies to lay in the range between 0.9 and 1.4 degrees C for the 2021 to 2050 period and 1.0 to 3.5 degrees C until 2100 (independent of the emission scenario, reference period 1971-2000). Precipitation projections made in various publications, on the other hand, yield a broad range of seasonal rainfall changes, which, at the moment, limits the possibility of reaching reliable conclusions concerning changes in groundwater recharge. However, averaged trends of multi-model ensembles indicate as a tendency a further increase of annual precipitation amounts by 4 to 7 %for the period 2021-2050 and by 1 to 11 % until 2100 (independent of the emission scenario, reference period 1971-2000).This development will likely be accompanied by a shift in rainfall amounts from summer to winter. Possible impacts of climate change on groundwater management include seasonal changes in both water availability and water demand and are already to be expected for the period 2021 to 2050. If adaption strategies are not implemented, the situation is likely to cause tensions in the water sector due to conflicts between sustainable management objectives and a climatically influenced changing societal groundwater demand.