Summary of the Article:

### Snow Layer Combination

When a snow layer has nearly melted or its thickness is less than the prescribed minimum, it is combined with a neighboring layer according to the following rules:

1. If the top layer is being removed, it is combined with the underlying layer.
2. If the underlying layer is not snow (i.e., it is the top soil layer), the layer is combined with the overlying layer.
3. If the layer is nearly completely melted, the layer is combined with the underlying layer.
4. If none of the above rules apply, the layer is combined with the thinnest neighboring layer.

After the combination, the layer properties (temperature, ice/liquid water content, thickness) are recalculated, and the snow water equivalent and depth are updated. If the snow depth is less than 0.01 m or the snow density is less than 50 kg/m³, the number of snow layers is set to zero, and the ice and liquid water contents are assigned to the top soil layer.

The article also provides a table with the minimum and maximum thickness of snow layers based on the number of layers.