Jonathan Macuroy, Wei-Yu Chang, D. Faustino-Eslava, Patricia Ann J. Sanchez, Cristino L. Tiburan Jr., B. Jou
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引用次数: 1
Abstract
The study analyzed the raindrop size distribution (DSD) measured by an optical Parsivel disdrometer in Southern Luzon, Philippines and utilized it to generate dual-pol relations for the nearby Tagaytay radar. The relations were generated using two methods (Method 1 - gamma-based and Method 2 - linear fitting), four time-integration steps (1, 2-, 5, and 10-min) and datasets from two periods (wet season and single event). The resulting quantitative precipitation estimates (QPEs) calculated from the generated R(Z) relations were compared to rain gauge stations near the disdrometer and were evaluated for the Tropical Storm Yagi Monsoon event of 10 August (2200 UTC) to 11 August (0400 UTC) 2018 using six statistics: Pearson’s correlation; mean error, percent bias, Nash-Sutcliffe Efficiency, mean absolute error, and root-mean-square error. Results show that the area’s DSD demonstrates relatively larger average raindrop diameters than some of its Asian counterparts, albeit a smaller number in the total number of raindrops when compared with the same areas. In terms of QPE evaluation, results showed a consistent pattern observed wherein the R(Z) relations using finer time steps (1-and 2-min) generally performed better than the longer ones. Moreover, Method 1 dominated Method 2 in terms of error statistics. As expected, Method 2 outperformed Method 1 in terms of r (as Method 2 itself is derived through linear fit). The best derived R(Z) relations were able to outperform other relations in terms of r, NSE, and RMSE. On the other hand, R(K DP ) was able to perform the best in terms of ME, MAE, and pBIAS, reducing the bias of current standard method by up to 74%.
期刊介绍:
The major publication of the Chinese Geoscience Union (located in Taipei) since 1990, the journal of Terrestrial, Atmospheric and Oceanic Sciences (TAO) publishes bi-monthly scientific research articles, notes, correspondences and reviews in all disciplines of the Earth sciences. It is the amalgamation of the following journals:
Papers in Meteorological Research (published by the Meteorological Society of the ROC) since Vol. 12, No. 2
Bulletin of Geophysics (published by the Institute of Geophysics, National Central University) since No. 27
Acta Oceanographica Taiwanica (published by the Institute of Oceanography, National Taiwan University) since Vol. 42.