Maximum wind speed data from PAGASA in the past 30 years: statistical analysis for engineering use

by Nicetos E. Rosaria & Benito M. Pacheco, 1999, Proceedings of the 8th ASEP International Convention, Manila, Philippines, Association of Structural Engineers of the Philippines (ASEP).


Abstract: The paper covers the statistical analysis made on the monthly maximum wind speed data from the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA).  The methods by which these data are recorded and their suitability for engineering use are evaluated.  Comparison of wind directions between the PAGASA-defined prevailing wind and the associated directions of the monthly maximum wind speeds were conducted.  The type of extreme value distribution for each station was determined by the "Peak over Threshold" approach.  By grouping the stations according to the typhoon-frequency zones that PAGASA established, we determined if the average number of typhoon passage affects the type of extreme value distribution for the zone.  The following conclusions were reached in the paper: (1) sufficient data suitable for extreme value analyses are available from PAGASA; (2) associated directions of the maximum wind speed data are principally active from the NE and SW directions, however a wind directional sensitivity analysis may still be required in the design of structures sensitive to wind effects; and (3) the Philippine as a whole could be best represented by a reverse Weibull type of extreme value distribution.