40 meters

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Discussion on Time Interval for Calculating Rain
rates For WMO Intercomparison Experiment Vigna Di
Valle
40 meters
Precipitation testbed at Sterling, VA USA The two
systems are 40 meters apart and are
identical. System consists of Geonor raingauge,
single alter shield and a small double fence
intercomparison shield. Inner ring is 12 feet
in diameter, outer ring is 28 feet in diameter.
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5 precipitation events were chosen to examine the
variability in calculating rain intensity from
two identical rain gauge configurations. In
addition, a brief examination of lag times
between two identical shield configurations but
different rain gauges for the same 5
precipitation events.
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The total rainfall amounts measured by both
systems for the 5 events agreed with each
other within 1.
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Time Lags Geonor1 vs. Geonor2 The time lag is
defined as the time when the precipitation
amounts from one gauge match those best from
another, when time-shifted by the lag amount.
The time of the minimum of the squares of
differences is this time. For Geonor1 vs.
Geonor2 the time lag for the 5 days is always 0
minutes Geonor1 vs. Ott706 The time lags for
Geonor1 vs. Ott706 are as follows June 1 4
minutes July 4 6 ½ minutes August 7
3 ½ minutes September 8 6 minutes October 20 4 ½
minutes
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This short study is meant to stimulate discussion
on how to compare The measured rainfall intensity
from dissimilar systems and the spatial
variability within the test plot.