Uncertainty in Measured Raindrop Size Distributions from Four Types of Collocated Instruments
| Autor: | Pay Liam Lin, GyuWon Lee, Wen-Chau Lee, Wei Yu Chang, Cheng-Ku Yu, Ben Jong-Dao Jou |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
010504 meteorology & atmospheric sciences
0207 environmental engineering 02 engineering and technology 01 natural sciences law.invention sampling volume Disdrometer disdrometer drop size distribution uncertainty measuring principle law Radar 020701 environmental engineering lcsh:Science 0105 earth and related environmental sciences Mathematics Remote sensing Observational error Sampling (statistics) Spectral density Covariance Measuring principle General Earth and Planetary Sciences Measurement uncertainty lcsh:Q |
| Zdroj: | Remote Sensing, Vol 12, Iss 1167, p 1167 (2020) Remote Sensing; Volume 12; Issue 7; Pages: 1167 |
| ISSN: | 2072-4292 |
| Popis: | Four types (2D-video disdrometer: 2DVD; precipitation occurrence sensor system: POSS; micro-rain radar: MRR; and Joss–Waldvogel disdrometer: JWD) of sixteen instruments were collocated within a square area of 400 m2 from 16 April to 8 May 2008 for intercomparison of drop size distribution (DSD) of rain. This unique dataset was used to study the inherent measurement uncertainty due to the diversity of the measuring principles and sampling sizes of the four types of instruments. The DSD intercomparison shows generally good agreement among them, except that the POSS and MRR had higher concentrations of small raindrops (5.2 mm). The measurement uncertainty ( σ ) was obtained quantitatively after considering the zero or non-zero measurement error covariance between two instruments of the same type. The results indicate the measurement uncertainties were found to be neither independent nor identical among the same type of instruments. The MRR is relatively accurate (lower σ ) due to large sampling volumes and accurate measurement of the Doppler power spectrum. The JWD is the least accurate due to the small sampling volumes. The σ decreases rapidly with increasing time-averaging window. The 2DVD shows the best accuracy of R in longer averaging time, but this is not true for Z due to the small sampling volume. The MRR outperformed other instruments for Z for entire averaging time due to its measuring principle. |
| Databáze: | OpenAIRE |
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