Simulation of Water Level Fluctuations in Kettle Holes Using a Time Series Model

Abstract

Kettle holes are widespread in moraine landscapes. Their hydrological properties may be very vulnerable to changes in climatic conditions. To increase our knowledge of how kettle holes function and how they may be affected by climate change requires a model that can be applied to a variety of them regardless of their properties. We used the PIRFICT time series model to simulate the water levels in kettle holes over the last 50 years. For model calibration we applied time series of two-year lengths. We observed correlations between climate indices and water level statistics with a delayed response of one year. The results show a decrease in autumn low water levels and an increase in water level fluctuations. These effects correspond to observed increased summer evaporation and winter precipitation, and imply that the habitat quality dynamic of kettle holes depends on climatic conditions. With the prognosis of even warmer and dryer summers in Europe in the future, conservation strategies for kettle holes should include the effects of climate change