References

ADGEO

Advances in Geosciences

ADGEO

Adv. Geosci.

1680-7359

Copernicus Publications

Göttingen, Germany

10.5194/adgeo-10-91-2007

Measurement of solid precipitation with an optical disdrometer

Lempio

G. E.

¹ Bumke

¹ Macke

Leibniz Institute of Marine Sciences (IFM-GEOMAR), Kiel, Germany

26 04 2007

10 91 97

2007

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A study about measurements of solid precipitation using an optical disdrometer is presented. The optical disdrometer is an improved version of the ODM 470 disdrometer. It allows to measure hydrometeors within a size range of 0.4 to 22 mm in diameter. <br><br> The main advantage of this instrument is its ability to estimate accurately precipitation even under strong wind conditions (Großklaus, 1996). To measure solid precipitation a geometrical model was developed to determine the mean cross-sectional area of snow crystals for different predefined shapes and sizes. It serves to develop an algorithm, which relates the mean cross sectional area of snow crystals to their maximum dimension, liquid water content, and terminal velocity. The algorithm was applied to disdrometer measurements during winter 1999/2000 in Uppsala/Sweden. Resulting precipitation was compared to independent measurements of a Geonor gauge and to manual measurements. In terms of daily precipitation the disdrometer shows a reliable performance.

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