The AIFS v1 model is trained on two datasets: ERA5 and IFS (operational analysis). The latter is used for fine tuning. The way soil temperature is represented in these datasets is different: there is a mask for oceans in the ERA5 Land dataset, while IFS data use interpolation to represent soil temperature over the oceans. We find that this difference greatly matters when it comes to precipitation results. What kind of representation of soil temperature should I use for inference for reliable precipitation results?