Global Climate Dynamics
Kosaka Laboratory

Exploring mechanisms of global linkages in climate variability to identify a key for climate prediction

Teleconnections link remote climate variations over the Earth

Regional disturbances in the atmosphere are transmitted to remote regions through changes in atmospheric circulati o n , a phenomenon called “teleconnection” . It forms through feedback processes that often involve ocean-atmosphere interactions, and induces further feedback in remote regions, sometimes leading to extreme weather events. Ocean variability evolves slowly compared to the atmosphere and influences climate worldwide from seasons to years, and even to decades. This process also provides a key for seasonal climate predictions.
Such natural climate variability interferes with human-induced climate change. On one hand, this can make heat wave even severer. On the other hand, it sometimes leads to regional cooling despite the ongoing global warming. Attribution of observed climate variability to human influence, which provides the basis for the reliability of predictions and has important implications for energy and climate policymaking, requires a deep understanding of natural variability and various numerical simulations of climate change.
We pursue understanding of global covariability of the climate system and identification of a key to climate predictability through analyzing observational and climate simulation data sets and designing and performing climate model simulations. Major research topics include

• (1) Mechanisms and predictability of extreme weather in East Asia arising from global-scale atmospheric circulation variability
• (2) Mechanisms of ocean-atmospheric variability in ocean basins and its global influence
• (3) Attribution of various climate change signals

Column
The PI of our laboratory is a fan of Doraemon. One day, after this became known to the lab members, a giant Doraemon plushie appeared in the lab. Since then, students and staff have continuously brought Doraemon merchandise, and now the lab is filled with Doraemon. The plushie sits as the centerpiece of the lab, providing comfort not only to the PI but also to the students and staff who come for discussions.


"The master of the laboratory. The left photo was taken when he first arrived at the laboratory, and the right photo shows his appearance in May 2024."

Member

• 
• • Associate Professor
    Yu KOSAKA
  Research Area: Climate variability, Extreme weather, Global climate simulation

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