New Papers PERSiST

Declining streamflow in central European forests

Dr. Jan Deutscher and colleagues present a new study modelling streamflow decline in the Central European uplands. This study is timely as in recent decades the effects of global climate change have caused a continuous drying out of temperate landscapes. In Czech forests, this drying out has been manifested as a visible decrease in streamflow. Dr. Deutscher and colleagues address questions related to the severity of the streamflow decrease and attempt to identify its main causes. They base their analysis on daily streamflow, temperature, and precipitation data measured during five years (1/11/2014 to 31/10/2019) in a spruce-dominated temperate upland catchment located in the Czech Republic. Streamflow values were modeled in with PERSiST using precipitation and temperature values obtained from the observational E-OBS gridded dataset and calibrated against in situ measured discharge. Their modeling results show a greater than 65% decline in streamflow during the five-year study period at the Křtiny experimental catchment. This trend is most likely caused by increasing temperature. They found a strong relationship between increasing temperature and decreasing discharge during the growing seasons, which can be simplified to an increasing trend in the mean daily temperature of 0.1o C per season, effectively causing a decreasing trend in the discharge of −10% per season regardless of the increasing precipitation during the period.