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Time of day for rain measurements

GLOBE students measure the current values of many environmental properties, but the Precipitation Protocol measures the total amounts and the Max/Min Atmosphere and Soil Temperature protocols measure the extremes that have occurred during the previous 24 hours. At the beginning of GLOBE, the time of day for these daily measurements was chosen as within one hour of local solar noon. The thought was that the middle of the school day would be an easy time to have students go outside and take data.

Today in GLOBE, the air and soil temperatures can be measured with the digital multi-day max/min thermometer, and the data can be taken at any time of day once the thermometer has been initiated. The measurements still record the daily maxima and minima that occur between local solar noon one day and the next. This leaves precipitation as the only GLOBE Protocol where students must visit their rain gauge in the middle of the school day.

In supporting SMAP with surface soil moisture measurements, the soil samples are collected by 9:00 AM because the satellite passes overhead at roughly 6:00 AM every third day. This is before the school day. Knowing daily rainfall measured at the same time would enable easier comparisons between rain and soil moisture. Would there be an advantage for teachers and schools in GLOBE, if there were an option to collect rain data before school as an alternative to the middle of the school day? 

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