John Frewen-Lord has caught a typo in my posting. That line should read: (1.2857 mm)(1.8 cm) = 0.7 mm/cm (note the prefix ratio)
Thank you, John! Jim On 2011-02-10 1009, James R. Frysinger wrote:
We've just had another snowstorm. This was part of a system that dropped large amounts of snow on the plains and the south. Our area experienced just the fringe of that system, though. I measured the depth of the accumulated snow as 1.8 cm. I gathered snow from an area measuring 14 cm by 25 cm and weighed it as amounting to 45 g. Calculations: Rainfall equivalent ---- (0.045 kg)/(0.14 m)(0.25 m) = 1.2857 kg/m2 (extra digits carried out) = 1.3 mm rain equivalent (assume 1 L of water is 1 kg of water) Ratio of snow to rain equivalent ---- (1.2857 mm)(1.8 cm) = 0.7 (note the prefix ratio) This was a nice "clean" snowfall, occurring entirely at temperatures below 0 °C and containing no slush, frozen rain, sleet, ice, etc. OFF TOPIC: I encourage each of you to look into joining CoCoRaHS as a volunteer. See http://www.cocorahs.org/ for details. It costs little, but a few minutes of your time each day would be very useful to NOAA and NWS. Click on your state in their map to see what station density occurs in your area; stations that have reported by that time (for that given date) will appear on the map. Orography and other factors are responsible for my station reporting results that differ greatly from other stations less than 30 km away! Unfortunately, the data must be entered in inches. I have corresponded with the man who runs CoCoRaHS and our state's coordinator (who works at NOAA) about this and they agree that metric is better. However, when setting up CoCoRaHS they feared that collecting the data in metric units would have resulted in many fewer volunteers. I am still pressing him to at least devise a data collection page that accepts metric units rather than requiring me to do conversions. Maybe you could join up and help make this program metric-friendly, at least! Jim
-- James R. Frysinger 632 Stony Point Mountain Road Doyle, TN 38559-3030 (C) 931.212.0267 (H) 931.657.3107 (F) 931.657.3108
