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Guest lecture: “Tropical-Arctic Climate Connection: Model Performance and Changes under Climate Change”.

Tidspunkt

13. august 2025, 09:00-10:00

Sted

Bjerknes meeting room 3180, Jahnebakken 5

On 13 August (11:00-12:00, Room 3180 on the third floor of West Wing of GFI),  our guest – Prof. Bo SUN - will present his work on “Tropical-Arctic Climate Connection: Model Performance and Changes under Climate Change”.

Dr. Bo Sun is a Professor at the Nanjing University of Information Science & Technology (NUIST), who is a group leader of the Key Research and Development Program Project  of China (‘Interaction between the Arctic Sea-Ice-Atmosphere System and the Tropical Sea-Atmosphere System and Connection with Global Warming’) and a group leader of the State Key Laboratory of Climate System Prediction and Risk Management of China. 

He earned his PhD from the University of Chinese Academy of Sciences in 2015 at the Institute of Atmospheric Physics. His research particularly focuses on the mechanisms of extreme weather events in China, atmospheric teleconnection patterns, and predictive modelling—anchored at NUIST within Academician Huijun Wang’s research group. His ResearchGate profile lists 78 publications, 20,773 reads, and over 1,750 citations, highlighting his active engagement in atmospheric and climate science research.

Abstract (authors: Bo Sun, Huijun Wang, Wanling Li, Wenchao Tang, Fei Li, Shengping He, Noel Keenlyside):

The Arctic-tropical climate connection has profound impact on the climate in Northern Hemisphere. The climate models are essential for understanding the mechanisms of Arctic-tropical climate connection and predicting the climate anomalies associated with Arctic-tropical climate connection. It still remains unclear about the performance of climate models in simulating the dynamic processes of Arctic-tropical climate connection and the potential reasons. In addition, notable changes have been observed in the climate system such as the impact of ENSO and Arctic sea ice on mid-latitude climate. Nevertheless, the changes in Arctic-tropical climate connection has been less understood. In our studies, the performance of CMIP6 models in simulating the dynamic processes of Arctic-tropical climate connection is evaluated, where the best models are selected. Furthermore, a reversal in the relationship between ENSO and Arctic surface temperature during spring under climate change is revealed, which is related to changes in the ENSO-triggered Rossby waves. These findings contribute to a better understanding of the Arctic-tropical climate conn

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