Snow CrystalSNOW HYDROLOGY (GEOG 4321): HOMEWORK ASSIGNMENT 5

Instuctor: Mark Williams
Telephone: 492-8830



Homework 5

We are going to examine radiation data from the Niwot Ridge LTER site in order see how the radiation balance of a mountain snowpack changes over the snow season. Go to the Niwot Ridge Data Catalog at http://culter.colorado.edu/. Enter the old site. Click on data. Click on Data set catalog and keyword/investigator search. Click on Subnivean Laboratory Data. Next click on Snowmelt and Meteorological Data from the Subnivean. Now go to Level 2D data. Acquire the Level 2D data from January through July 2000 (0001 to 0007). To complete the question, you will need the 4 components of Net Radiation (Incident and Reflected Shortwave and Atmospheric and Terrestrial Longwave) as well as measured Net Radiation. Under Data Level Selection, check Level 2D (Daily).  Under Radiometric Data, select the five components listed above. Click Send Document. Next select either viewing option to work with the data. Using this data create three graphs:
  1. Create 3 graphs with the data you obtained (15 points):
  2. Describe the trends in net radiation. When does net radiation become positive? When does it peak? Why? (5 points).
  3. How does the relationship between incident and reflected shortwave change over the season? Calculate an albedo value for one day in February, May, and July. How and why are they different? (10 points)
  4. What is the relationship between incoming and outgoing longwave over the season? Is longwave more or less variable than shortwave? Take a guess at why this is. (5 points).
  5. Overall, what factors are most responsible for the seasonal increase in net radiation measured at Niwot Ridge? (5 points).