Measuring Snow Properties:Albedo, Depth, Density, and Temperature Elizabeth Burakowski, UNH firstname.lastname@example.org September 2012
Equipment Field NotebookScraper or Spatula IR Temperature Gun Pyranometer on leveling boom 2-ft and 4-ft snow tubes with caps Digital Hanging Yardstick Scale
Where to Measure• In an level open area, with minimal shadingfrom trees, houses, fences, etc.• Undisturbed snow pack (no footprints, pet waste, etc)• Point leveling boom at sun (south) to reduce shadowing• If snowpack is thin or patchy, pick an area that is most representative of overall snow conditions.• Measurement areaisabout 1 m2
When to Measure• Collect daily snow-coveredand snow-free measurements frombeginning of November until end of snow season.• Try not to miss measurements on clear sky days. These days are most important for satellite validation.• Begin daily data collection 1 hour of Local Solar Noon: http://www.esrl.noaa.gov/gmd/grad/solca lc/.
What to Measure 1. Albedo 2. Snow Depth 3. Snow Density 4. Snow Temperature
How To Measure Albedo1. Identify area to measure and approach from north (do not trample your sampling area).2. Point leveling boom south with pyranometer facing upward, use bubble at hip to level. Record UP1.3. Flip boom and level at hip with MP-200 facing downward. Record DOWN1.4. Repeat steps 3 & 4 two more times, for total of three up & down paired measurements.5. Turn off pyranometer and replace green cap. Record other values (e.g., cloud and snow conditions)
How To Measure AlbedoPlease remember to record the following atthe time of albedo measurement:Start Time (HH:MM) and End Time (HH:MM)Cloud Cover:OVC- overcastPCL – partly cloudyCLR – clearACLR – all clear or blue bird. 0% cloud cover.Snowmelt: Yes or no.Snowing: Yes or no.Snowfall in past 24 hours: Yes or No.Comments: passing clouds or haze, grass or vegetation showing, debris on snow, raining.
How To Measure Albedo1. Power button 22. Meter read-out (in Watts/m23. No need to use 3 these buttons. Sensor will display values instantly.
Batteries for PyranometerThe Apogee MP-200 takes one Renata Lithium CR2320 battery. One battery should last you the whole winter.If necessary, we will send you a replacement battery.
How to Measure Surface Temperature1. Make sure the IR gun is set to measure in oF by pressing the scale selector button2. Point the IR temperature gun vertically about 3 inches above the surface.3. Press the measure button for 5 seconds and record the temperature displayed on the screen.4. Hold the gun steady and level for best results. If the temperature changes, pick the average number of the displayed values.
How to Measure Snow Depth 1. Place the snow tube (2-ft or 4-ft) vertically into the snow pack, making sure the hanging hole is at the top end of the tube. 2. Scrape snow off the side of the tube and measure snow depth to ground, rounding to nearest 0.5”. If you are unable to reach the ground surface (i.e., ice layer at bottom of tube), record the snow depth collected in the tube and note approximate thickness of ice not collected in tube.
How to Measure Snow Density1. Place spatula under bottom of tube, lift way from the snowpack and carefully secure cap on bottom of tube. Bring the tube indoors to weigh (scale does not work well in cold weather).2. Hang the scale from a sturdy hook. Turn on the scale and watch for 0.000 lb to appear. (Hit MODE button to switch from kg to lb).3. Hang tube on metal scale hook, using hole at the top of the tube. Measure to nearest hundredth (0.00). Record the total weight (tube, caps and snow!) in lab notebook.
Data Entry MM/DD/YYYY HH:MM (24-hr clock) ACLR (0%); CLR (1-30%); PCL (31-60%); OVC (>60%) Remember, incoming should always be greater than outgoing. In oF Nearest 0.5 inch Nearest 0.00 lb (with snow and caps) Yes/No Nearest 0.00 lb (empty tube and caps) Note passing clouds or haze, vegetation showing through snowpack, leaf litter or debris on snow pack, snow grain texture (i.e., corn snow, light and powdery), etc.
How To Measure1. Identify area to measure and approach from north. Think Snow!2. Point leveling boom south with MP-200 facing Questions? upward, use bubble at hip to level. Record UP1.3. Flip boom and level at hip with MP-200 facing downward. Record DOWN1.4. Repeat steps 3 & 4 two more times, for total of Contact: Lizmeasurements. three up & down paired Burakowski5. Turnelizabeth.email@example.com off MP-200 and replace cap. Record other comments (e.g., cloud and snow conditions)6. Enter recorded values on CoCoRaHS.org