Measuring Snow Properties: Albedo, Depth & Density Elizabeth Burakowski, UNH firstname.lastname@example.org 14-May-2012
EquipmentScraper or Spatula Digital Hanging Scale Field Notebook 2-‐? and 4-‐? snow tubes with caps Pyranometer on leveling boom Yards:ck
Where to Measure• In an level open area, with no shading from trees, houses, fences, etc.• Undisturbed snow pack (no trampling by boots, 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 area should be about 1 m2
When to Measure• Collect daily snow-covered and snow-free measurements from first snowfall until end of snow season.• Take measurements under clear sky and overcast conditions. Partly cloudy days passing clouds affect measurements.• Begin daily data collection ±30 min of Local Solar Noon:• http://www.esrl.noaa.gov/gmd/grad/ solcalc/.
How To Measure1. 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)6. Enter recorded values at www.albedo.csrc.dev
How To MeasurePlease also remember to record the followingat the time of albedo measurement:Start Time (HHMM) and End Time (HHMM)Cloud Cover: OVC- overcast PCL – partly cloudy CLR – clear ACLR – all clear or blue bird. 0% cloud cover.Snowmelt: Yes or no.Snowing: Yes or no.Comments: passing clouds, grass or vegetation showing, debris on snow, etc.
How To Measure1. Power button 2 2. Meter read-out (in Watts/m23. No need to use 3 these buttons. Sensor will display values instantly!8
BatteriesThe Apogee MP-200 takes one RenataLithium CR2320 battery. One batteryshould last you the whole winter.If necessary, we will send you areplacement battery.
Snow Depth1. After you’ve measured albedo, take a snow depth measurement from an area representative of your albedo measurement area.2. Place tube (2-ft or 4-ft) vertically into the snow pack.3. 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.
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 if in kg to switch).3. Hang tube on metal scale hook, using hole at the top of the tube. Measure to nearest hundreth (0.00). Record the total weight (tube, caps and snow!) in lab notebook.
Data Entry1. Select your CoCoRAHS sta:on number from the drop-‐down list. 2. Start and end observa:on :me apply speciﬁcally to albedo measurements. 3. Cloud cover at :me of albedo observa:on 4. An error will occur if your outgoing (reﬂected) value is greater than incoming. 5. Snow depth is depth of snow collected in the tube. Note depth of any snow/ice unable to be collected in tube in the observa:on notes sec:on. 6. Snow tube tare weight is the weight of the empty, dry tube with caps (to be made daily). 7. Snowmelt since last observa:on (yes/no) 8. Include comments on grain size, patchiness, leaf liVer and debris in observa:on notes.
How To Measure1. Identify area to measure and approach from north. Questions?2. Point leveling boom south with MP-200 facing upward, use bubble at hip to level. Record UP1.3. Flip boom and level at hip with MP-200 facing downward. Record DOWN1. Contact: Liz Burakowski4. Repeat steps 3 & 4 two more times, for total of email@example.com three up & down paired measurements.5. Turn off MP-200 and replace cap. Record other comments (e.g., cloud and snow conditions)6. Enter recorded values on CoCoRaHS.org
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