Looks as though it is ~1-5/8" on the left...but not on the right.
This is clearly a 6" ruler, so the clear part above on the left is (6" - 1-5/8") = 4-3/8" or 4.375" * (2.54 cm/") = 11.112 cm.
On the right, there is about 10.7 cm, so a difference of ~0.4 cm. The arithmetic average amount of free area is 10.9 cm, or 10.9 cm * (1"/2.54 cm) = 4.291".
So the average snow height is about (6" - 4.291") = 1.709" or a little over 1-11/16".
