Rain Gauge accuracy experiment

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rjd1000
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Rain Gauge accuracy experiment

Post by rjd1000 » Sat Nov 12, 2016 4:27 pm

i have a manual 5 inch copper gauge vs a fully calibratable electronic 0.1mm tipping bucket gauge vs a 4 inch plastic climeMet manual gauge. All 3 are next to each other and all at 1ft above the ground

started on the 1st november and will do it to the end of the month.

so far.

Copper 5" 35.1mm

Tipping 34.9mm

ClimeMet 33.5mm

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rjd1000
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Re: Rain Gauge accuracy experiment

Post by rjd1000 » Fri Dec 02, 2016 7:11 pm

Final Results for November 2016

Copper 5" 119.4mm

Tipping 120.4mm

Climemet 112.5mm

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Paul C
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Re: Rain Gauge accuracy experiment

Post by Paul C » Mon Dec 05, 2016 8:27 pm

Are you assuming Copper is correct ?

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rjd1000
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Re: Rain Gauge accuracy experiment

Post by rjd1000 » Tue Dec 06, 2016 12:14 am

Paul C wrote:Are you assuming Copper is correct ?
interesting question.

is there such a thing as a correct figure?

Very little between the tipping and copper, and the plastic climemet was obviously a tad behind

as the copper 5" is the standard, figure id have to use that in comparison i guess

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Paul C
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Re: Rain Gauge accuracy experiment

Post by Paul C » Tue Dec 06, 2016 8:45 pm

OK - I think thats the best way

Converted to a percentage

Tipping Bucket 100.8 % ( I would have thought acceptable)
Climemet 94.2% ( well below error margin )

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rjd1000
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Re: Rain Gauge accuracy experiment

Post by rjd1000 » Tue Dec 06, 2016 10:04 pm

how does your vp2 compare to your 5" manual?

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wmb
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Re: Rain Gauge accuracy experiment

Post by wmb » Tue Dec 06, 2016 10:25 pm

Non will be correct. Rainfall/ppt is incredibly difficult to measure accurately, if you are getting within 10% agreement I wouldn't worry. I've read in exposed sites, 30% errors could occur due to wind eddies (on windy sites gauges should be in pits with top of gauge at ground level).

If rain fell with no wind and came down vertically and didn't evaporate, or fall as snow you may be able measure it accurately!

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