Comparison of Different Tropical Cyclone Datasets in the Northwestern Pacific Ocean Based on the Statistical Analysis

Abstract

Proper understanding of the characteristics of the historical tropical cyclones (TC) is of great importance for disaster prevention and mitigation efforts. Statistical analysis using existing data is an effective approach to analyze the characteristics of TC parameters. Nevertheless, different agencies provide different datasets of cyclones in terms of contents and accuracy. In this study, two historical datasets covering the period of 1951-2017 for the Northwestern Pacific Ocean TCs from the China Meteorological Administration (CMA) and Japan Meteorological Agency (JMA) are compared with the focus on TC frequency, intensity, track and drift velocity. It is found that annual TC frequency gradually decreases after 1951, whereas the annual average maximum sustained wind (MSW) decreases before 1977 and keeps stable afterward. In general, JMA provides relatively larger MSW values than CMA data, but CMA presents more large-magnitude MSW data (corresponding to super typhoon) than JMA. It is confirmed that the super typhoon frequency increases after 1977. Statistical study using the minimum sea level pressure is demonstrated to be not a suitable proxy for TC intensity. Meanwhile, the annual average difference in TC positions in 1972-1987 is larger than those of other periods owing to the non-uniform data processing approach. Annual average drift velocity of JMA is slightly larger than that of CMA in 1951-2017, but similar temporal variations are confirmed. The predominant TC drift direction is WNW. CMA provides larger probability density than JMA for the westward moving TC, whereas an opposite scenario occurs for the eastward moving TC. Taking into account the technical differences and non-uniform data processing approaches applied in determining TC parameters of different datasets, data before 1988 should be used with significant cautions to avoid obtaining the misleading results.