To overcome the limitation of low network density and sparse distribution of meteorological stations, spatial interpolation is being performed for estimating meteorological variables that are not geographically covered by existing observation network. While there are several readily available spatial interpolation techniques, it is still difficult to determine which one best estimates actual observation. Considering the stimulus for disaster risk reduction, hydrological, agricultural, and other applications of interpolated data, this study compared six interpolation techniques (Inverse Distance Weighted (IDW), Completely Regularized Spline (CRS), Tension Spline (TS), Ordinary Kriging (OK), Universal Kriging (UK), and ANUSPLIN) that have been recommended in tropical maritime region. Validation results comparing historical monthly and interpolated rainfall data from 1981−2010 in 65 stations in the Philippines show that OK has the best performance among the aforementioned techniques followed by ANUSPLIN and TS. Ultimately, this study is a contribution to the existing inadequate literatures that have documented and evaluated interpolation techniques that can be used in archipelagic regions with prominent climate variability.(Citation: Basconcillo, J. Q., G. A.

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Due to less tropical cyclone (TC) occurrences, the climatology of the quiescent TC season (i.e., March-April-May, MAM) in the Western North Pacific (WNP) is less understood when compared to the more active season (i.e., June-November). Here we show observational evidence of significantly decreasing TC quiescence during MAM that can be attributed to more Central Pacific El Niño events from 2002 to 2022. A Central Pacific El Niño is related to an asymmetric sea surface temperature (SST) pattern where warm (cool) SST anomalies are concentrated in the central (western) Pacific, which consequently contributes to the overall decrease in TC quiescence in MAM. Such anomalous SST pattern prompts the Western North Pacific Subtropical High to expand westward, creating a conducive large-scale environment for TC development and allowing TCs to move closer to the landmass, which ultimately leads to an increasing cost of TC-associated damages during the quiescent season. Our study provides new insights into the decreasing TC quiescence and TC climatology in the WNP during MAM, which is ultimately expected to contribute to disaster risk reduction in the region.