題目：西北太平洋反氣旋——夏季亞洲季風區季節內至年際尺度基本模態
報告人：王旭棟，沐鸣2博士後🚿，合作導師張人禾教授。於2021年獲得南京信息工程大學氣象學博士學位🌛，導師管兆勇教授和謝尚平教授🕵🏼♀️。主要研究方向為海氣相互作用🧍🏻、熱帶大氣季節內振蕩和季風動力學等🙆🏽。
摘要🧍：亞洲夏季風跨時間尺度變率的特征及其氣候影響一直是國內外相關領域研究的熱點🦴。本研究指出夏季西北太平洋反氣旋是印太暖池區大氣季節內至年際尺度跨尺度共有基本模態，受局地大氣波流相互作用和對流反饋過程影響🙇🏿♀️。年際尺度的西北太平洋反氣旋與ENSO準兩年周期存在密切聯系🌳；季節內尺度的西北太平洋反氣旋符合MJO的“水汽模”理論✯，主要向北傳播影響亞洲季風區氣候變率。此外🧏♂️，本研究還從跨尺度基本模態角度出發，簡單探討了2016與2020年亞洲夏季風異常的特征和形成機理。
題目🛁：A Multidecadal-Scale Global Teleconnection over the Past Millennium and Its Recent Impacts on Tropical Cyclone Activity
報告人🛠：Dr. Xiaofang Feng is a postdoctoral scholar at the Department of Atmospheric and Oceanic Sciences and the Institute of Atmospheric Sciences, Fudan University. She holds a Ph.D. degree in Meteorology from Nanjing University of Information Science and Technology (NUIST), and has been as a Joint Ph.D. student at the Department of Geography, University of California, Santa Barbara (UCSB). She obtained a M.S. degree in Meteorology from NUIST, and a B.S. degree in Atmospheric Sciences from Guangdong Ocean University. Her research interests are in tropical cyclone dynamics, climate variability and change in Large-scale atmosphere/ocean systems, paleoclimate, future climate change, and coupled climate modeling.
摘要👱🏻♀️：In the past 40 years, the global annual mean surface temperature has experienced a nonuniform warming. It exhibits significant asymmetry between the Arctic and Antarctic, with intermittent and spatially varying warming trends along the Northern Hemisphere (NH) mid-latitudes and a slight cooling in the tropical eastern Pacific. Here, we show that these nonuniform features are likely tied together by tropical eastern Pacific sea surface temperatures (SSTs), via a global atmospheric teleconnection. This tropically driven teleconnection is associated with a Pacific SST pattern resembling the interdecadal Pacific oscillation (IPO), and hereafter referred to as the IPO-related bipolar teleconnection (IPO-BT). The IPO-BT mode can be consistently obtained as a leading circulation mode over the past 100, 400 and 2000 years, which may serve as an important internal mode that regulates climate variability on multi-decadal scales. The spatial nonuniformity of recent temperature trends may be partially explained by the enhanced appearance of the IPO-BT mode by a transition of the IPO toward a cooling phase in the eastern Pacific in the past decades. Further, this internal mode plays a role in the recent shift of the basin-wide mean location of tropical cyclone (TC) formation in the western North Pacific (WNP). The poleward shift of the mean latitude of TC formation is accompanied by westward retreat of the monsoon trough (MT) and westward extension of the tropical upper tropospheric trough (TUTT), which is closely associated with IPO-related SSTs. Thus, low-frequency SST variability in the tropical Pacific acts as an important internal dynamical source to jointly regulate recent climate variability along with anthropogenic forcing.
