Journal of Tropical Oceanography ›› 2024, Vol. 43 ›› Issue (1): 64-78.doi: 10.11978/2023044CSTR: 32234.14.2023044

• Marine Meteorology • Previous Articles     Next Articles

Variation and mechanisms of autumn tropical cyclones landed in Guangdong

HAN Dingyan1,2(), LI Min1,2,3, HU Rui1, XIE Lingling1,2,3()   

  1. 1. Laboratory of Coastal Variation and Disaster Prediction, College of Ocean and Meteorology, Guangdong Ocean University, Zhanjiang 524088, China
    2. Key Laboratory of Climate, Resources and Environment in Continental Shelf Sea and Deep Ocean of Department of Education of Guangdong Province, Zhanjiang 524088, China
    3. Key Laboratory of Space Ocean Remote Sensing and Applications (LORA), Ministry of Natural Resources, Zhanjiang 524088, China
  • Received:2023-04-06 Revised:2023-06-09 Online:2024-01-10 Published:2024-01-19
  • Supported by:
    National Natural Science Foundation of China(42276019); Guangdong Science and Technology Plan Project (Observation, Tropical Marine Environment in Yuexi)

Abstract:

Using the track data of landed tropical cyclones (TCs) during 1949—2021 from Shanghai Typhoon Institute of China Meteorological Administration, this study analyzes the variation and mechanism of TCs landed in autumn in Guangdong area, and compares with the results in summer. The results show that a total of 76 TCs landed in Guangdong in autumn during the past 73 years, accounting for 28.5% of the landed TCs in whole year. The landed TCs in autumn (ALTCs) are mostly in categories of strong typhoon and super typhoon, and the mean peak intensities are stronger than those in summer. 72.4% of the ALTCs generated in the Western North Pacific, a higher portion than summer landed TCs and the average latitude and longitude of TCs generation move southward and eastward. The yearly power dissipation index (PDI) of autumn TCs reaches 0.4×107m3·s−2, comparable to that of summer TCs; during landfall to dissipation, the average duration time of autumn TCs is less, the translation speed is slower and PDI is less than those of summer TCs. In long-term variations, the declining trend and decrease rate of the number of ALTCs is similar to that in summer, while the landing intensity of ALTCs increases with a rate 1.8 times higher than that in summer. The translation speed of ALTCs slows down but with a rate 2.5 times lower than summer TCs, the PDI of ALTCs shows a weaker decreasing trend than summer TCs. Unlike more TCs landed in summer in La Niña year, more ALTCs appeared in El Niño years. The number of ALTCs is related to the ENSO (El Niño-Southern Oscillation) index in previous winter and spring with correlation coefficient of about 0.3. It can be used as an indicator for next-year ENSO prediction. In decadal variability, the correlation coefficients between the number of ALTCs and the PDO (Pacific Decadal Oscillation) index, were -0.51 and 0.68 in the warm phase (1977—1996) and cold phase (1997—2016), respectively. The composite analysis shows that ALTCs can occur with a warm sea surface temperature anomaly in the northern South China Sea, which induced cyclonic atmospheric circulation in the South China and favors TCs landed in Guangdong.

Key words: landed tropical cyclone in autumn, long-term variation, interannual variability, ENSO