Environmental characteristics of western North Pacific tropical cyclone onset in neutral ENSO years
Por:
Gao J., Zhao H., Klotzbach P.J., Sun F., Raga G.B., Wang C., Ma Z.
Publicada:
1 ene 2023
Ahead of Print:
1 nov 2022
Categoría:
Atmospheric science
Resumen:
This study investigates the inter-annual changes in tropical cyclone season onset (TCSO) over the western North Pacific (WNP) in neutral El Niño-Southern Oscillation (ENSO) conditions during 1979–2019. The average TCSO during early TCSO years (~ March 27) is significantly earlier than during late TCSO years (~ June 18). In response to inter-annual changes of TCSO in neutral ENSO years, TC activity shows distinct seasonal features. Although there are no significant differences in total TC counts, more TCs occur in March–May while fewer TCs occur in September–November during early TCSO years. Additionally, TC genesis locations tend to move eastward and equatorward during early TCSO years. These TCs are also found to have stronger lifetime maximum intensities. Changes in seasonal TC activity are closely associated with changes in the large-scale environmental pattern changes, which are driven by the seasonal evolution of sea surface temperature anomalies (SSTAs). Low-level vorticity and mid-level humidity changes are found likely to be the two primary factors inducing the seasonal feature differences between early and late TCSO years. Further analyses suggested that the seasonal evolution of sea surface temperature anomaly patterns over the tropical Indian Ocean and tropical Pacific accompanied by TCSO in neutral years is closely linked to changes in the spring Pacific Meridional Mode. Observational analyses and numerical simulations suggest that the Pacific Meridional Mode mainly causes changes in the low-level large-scale circulation over the tropical WNP via a Rossby wave Gill-type response, thus affects inter-annual variability of TCSO during neutral ENSO years. This response is found to be distinct from the previously documented strong relationship between TCSO and strong ENSO events. © 2022, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.
Filiaciones:
Gao J.:
Key Laboratory of Meteorological Disaster, Ministry of Education (KLME)/Joint International Research Laboratory of Climate and Environment Change (ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disaster (CIC-FEMD)/Pacific Typhoon Research Center/Earth System Modeling Center, Nanjing University of Information Science and Technology, Nanjing, China
Zhao H.:
Key Laboratory of Meteorological Disaster, Ministry of Education (KLME)/Joint International Research Laboratory of Climate and Environment Change (ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disaster (CIC-FEMD)/Pacific Typhoon Research Center/Earth System Modeling Center, Nanjing University of Information Science and Technology, Nanjing, 210044, China
Klotzbach P.J.:
Department of Atmospheric Science, Colorado State University, Fort Collins, CO, United States
Sun F.:
School of Science and Engineering, University of Missouri, Kansas, MO, United States
Raga G.B.:
Centro de Ciencias de la Atmósfera, Universidad Nacional Autónoma de México, Mexico, Mexico
Wang C.:
Key Laboratory of Meteorological Disaster, Ministry of Education (KLME), Nanjing University of Information Science and Technology, Nanjing, 210044, China
Ma Z.:
College of Meteorology and Oceanography, National University of Defense Technology, Changsha, China
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