Two ABe 4/4 II EMUs are pulling "Räumer" 9132, which scrapes snow off the sides onto the track, such that the snow can then be removed by the rotary Xrot d. The point of this is to create enough space such that additional snow can be cleared using conventional plows - until the space fills up.
At least that's how snow clearing worked until recently when they got the new X rot mt (see here), which can be extended to both sides, but still needs two passes to clear the entire width.