Japan Geoscience Union Meeting 2025

Presentation information

[E] Oral

A (Atmospheric and Hydrospheric Sciences ) » A-AS Atmospheric Sciences, Meteorology & Atmospheric Environment

[A-AS03] Extreme Events and Mesoscale Weather: Observations and Modeling

Tue. May 27, 2025 9:00 AM - 10:30 AM Exhibition Hall Special Setting (5) (Exhibition Hall 7&8, Makuhari Messe)

convener:Tetsuya Takemi(Disaster Prevention Research Institute, Kyoto University), Sridhara Nayak(Japan Meteorological Corporation), Ken-ichi Shimose(National Research Institute For Earth Science and Disaster Resilience), Takumi Honda(Information Technology Center, The University of Tokyo), Chairperson:Tetsuya Takemi(Disaster Prevention Research Institute, Kyoto University)

10:00 AM - 10:15 AM

[AAS03-05] The type of extreme weather in cold versus warm climate regimes: evidence from historical and modern climate data

★Invited Papers

*Pao K. Wang1 (1.Research Center for Environmental Changes, Academia Sinica, Taipei, Taiwan)

Keywords:extreme weather, convective storms, cooling and warming climate regimes, historical climate data

Recent climate model studies often predict the occurrence of extreme weather or climate conditions under certain global warming scenarios using climate models. However, it is usually unclear about the nature of such extreme events and how such weather extremities occur as the resolution of the current generation climate models is usually not high enough to resolve individual storm systems let alone pinning down their physical mechanisms. This ambiguity in physical mechanism impedes the better understanding of the nature of these extreme weather/climate events and can lead to ineffective mitigation and/or adaptation measures. For example, when the term extreme rainfall is mentioned, it is unclear whether it is caused by severe convective storms or by regular storms that have higher liquid water contents (LWC), as both can lead to large amount of rainfall. But the detailed physical mechanisms of these two types of storms are different. Clearly it is desirable to remove such ambiguity and clarify what type of storms would occur in certain climate regime.
In this study, we utilize the meteorological series derived from the REACHES climate database compiled from Chinese historical documents (Wang et al., 2018) as well modern weather data to pin down the type of storms and to study the respective physical mechanisms responsible for the extreme events that preferably occur in cold versus warm climate regime. We use the REACHES reconstructed temperature series in China in 1368-1911 (Wang et al., 2024) and construct convection index series using other information (such as lightning) in REACHES database to show that the severe deep convective storms are the preferable type that causes extreme weather events in cold climate regime and utilize modern observational data to demonstrate that the high LWC (but not necessarily severe) storms are the type most likely to lead to extreme events in warming climate.
Finally, physics-based storm model simulation results will be used to illustrate the dynamical processes of and key parameters in these two types of extreme weather and explain why they lead to different patterns.