Study on the differences between CMA and JTWC tropicalcyclone datasets for northwest Pacific

By using two tropical cyclone datasets for northwest Pacific (NWP) of China Meteorological Administration (CMA) and Joint Typhoon Warning Center (JTWC), the differences with respect to TC location and intensity between them were analyzed. Results showed that for TC location, large discrepancies existed in two periods: 1951-early 1960s and 1988-1990s, and geographically always appeared in regions where TC landed or highlatitude areas. For TC intensity, the CMA dataset was apparently overestimated in 1950s and from the late 1960s to the early 1970s, while the JTWC dataset overestimated in 1993-2003. TC Intensity discrepancies showed scattered large values in different regions before 1980s, after which with the increase of intensity for JTWC dataset, it was significantly greater than that of CMA dataset in most of NWP, while the latter was greater in the coast regions of East Asia. Further analysis reveals that the discrepancies are obviously related to the TC observational techniques. Before the era of application of meteorological satellite in operational typhoon Centers (1951-early 1960s), and after the termination of aircraft reconnaissance (1988-), large discrepancies existed in not only TC intensity but also TC location. The smaller discrepancies period (1973-1987) for TC intensity also coincided with timeframe when aircraft reconnaissance data and the Dvorak technique were both available in TC operational centers. For the two TC datasets, although obvious discrepancies existed between them, each had its own characteristics. Currently, it is still difficult to judge which one is better, but for TC activities affecting China, the CMA dataset has obvious advantages.