The authors would like to express their gratitude to René Fehlmann for providing the PV inversion routine and support with an early version of the simulation setup and to Daniel Lüthi for expert help with the EM model. The neat deduction leading to Eq. (16) was pointed out to us by one of the reviewers. We thank ECMWF and MeteoSwiss for providing access to the meteorological data. This study was conducted in part with funding from the NCCR Climate program of the Swiss National Science Foundation.
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