Bunzel, F., Mueller, W.A., Dobrynin, M., Froehlich, K., Hagemann, S., Pohlmann, H., Stacke, T., & Baehr, J. (2018): Improved Seasonal Prediction of European Summer Temperatures With New Five-Layer Soil-Hydrology Scheme. Geophysical Research Letters, Vol. 45 (2018) 1, 346-353, doi:10.1002/2017GL076204
We evaluate the impact of a new five-layer soil-hydrology scheme on seasonal hindcast skill of 2 m temperatures over Europe obtained with the Max Planck Institute Earth System Model (MPI-ESM). Assimilation experiments from 1981 to 2010 and 10-member seasonal hindcasts initialized on 1 May each year are performed with MPI-ESM in two soil configurations, one using a bucket scheme and one a new five-layer soil-hydrology scheme. We find the seasonal hindcast skill for European summer temperatures to improve with the five-layer scheme compared to the bucket scheme and investigate possible causes for these improvements. First, improved indirect soil moisture assimilation allows for enhanced soil moisture-temperature feedbacks in the hindcasts. Additionally, this leads to improved prediction of anomalies in the 500 hPa geopotential height surface, reflecting more realistic atmospheric circulation patterns over Europe.