1. Snow Depth Property with potentially largest variation in space

2. Snow Depth Property with potentially largest variation in space Measure vertical to earth’s surface

3. Snow Depth Property with potentially largest variation in space Measure vertical to earth’s surface

4. Snow Depth Property with potentially largest variation in space Measure vertical to earth’s surface

5. Snow Depth Property with potentially largest variation in space Measure vertical to earth’s surface

6. SWE measurement Mass of water over a unit area –Weigh cylindrical snow sample Typically the Mt. Rose or Federal Sampler is used A gravimetric technique

7. SWE measurement 1.Clean the snow tube of debris, snow, etc. cutter/teeth snow tube

8. SWE measurement 1.Clean the snow tube 2.Tare the snow tube scale snow tube cutter/teeth

9. SWE measurement 1.Clean the snow tube 2.Tare the snow tube scale snow tube

10. SWE measurement 1.Clean the snow tube 2.Tare the snow tube 3.Insert tube vertically

11. SWE measurement 1.Clean the snow tube 2.Tare the snow tube 3.Insert tube vertically 4.Rotate tube into snowpack

12. SWE measurement 1.Clean the snow tube 2.Tare the snow tube 3.Insert tube vertically 4.Rotate tube into snowpack 5.Twist sharply at bottom

13. 1.Clean the snow tube 2.Tare the snow tube 3.Insert tube perpendicular 4.Rotate tube into snowpack 5.Twist sharply at bottom 6.Pull out vertically SWE measurement

14. 1.Clean the snow tube 2.Tare the snow tube 3.Insert tube perpendicular 4.Rotate tube into snowpack 5.Twist sharply at bottom 6.Pull out vertically 7.If an entire column has been removed, weigh tube with core SWE measurement

15. 1.Clean the snow tube 2.Tare the snow tube 3.Insert tube perpendicular 4.Rotate tube into snowpack 5.Twist sharply at bottom 6.Pull out vertically 7.If an entire column has been removed, weigh tube with core SWE measurement

16. Snowpack Density Average density = SWE / depth

17. Snowpack Density Stratified densities from snow pits 1.Dig a pit to the bottom 2.Include a stairway 3.Cut a straight face along the southern wall 4.Measure total depth 5.From top or bottom, measure densities at 10cm intervals 6.Concurrently measure temperature

18. Snowpack Density Kelly Cutter density sample extracter:

19. Snowpack Density Kelly Cutter density sample extracter:

20. Snowpack Density Kelly Cutter density sample extracter:

21. Snowpack Density 5.From top or bottom, measure densities at 10cm intervals –Clean wedge-shaped sample extracter (Kelly cutter) –Tare sample extracter –Insert sampler vertically to sample wall with bottom parallel to the ground –Slide plate along open side of sampler –Pull sampler and plate from wall –Remove excess snow from bottom and side of sampler –Weigh sampler and sample –Density = mass / volume

22. Snowpack Density Line up sampler perpendicular face of pit wall PLAN VIEW

23. Snowpack Density Insert sampler perpendicular PLAN VIEW

24. Snowpack Density Insert sampler perpendicular PLAN VIEW

25. Snowpack Density Insert sampler perpendicular Do not push into snow wall PLAN VIEW

26. Snowpack Density Slide lid along open face PLAN VIEW

27. Snowpack Density Slide lid along open face PLAN VIEW

28. Snowpack Density Slide lid along open face PLAN VIEW

29. Snowpack Density Extract sampler perpendicular PLAN VIEW

30. Snowpack Density Extract sampler perpendicular PLAN VIEW

31. Snowpack Density Volume of Kelly cutter = 1 L  Mass of sample = density

32. Shallow Snowpacks Less snow, potential for greater relative variation Take measurement large cores –eg. MSC sampler with  = 7.8 cm Smaller stratified samplers –eg. 250 – 500 ml Kelly cutter