Weather regimes are persistent, quasi-stationary, and recurrent large-scale circulation patterns, which may cause long-lasting cold spells, heat waves or torrential rain and flooding. Though weather regimes in the European region are a field of active research, only a few studies have analysed the dynamics and predictability of weather regimes in Japan. The newly established and DAAD-funded research project “Weather regimes in Europe and Asia: subseasonal predictability (WEASP)” aims to close this gap and advance the predictability of East Asian weather regimes on subseasonal timescales. To this regard, the members of the “Large-scale dynamics and predictability group” welcomed three colleagues from University of Tsukuba (Japan), Mio Matsueda (Assistant Professor), Akio Yamagami (PostDoc), and Takumi Matsunobu (MSc Student) for a one-week stay at KIT.
Scientifically, the visit entailed fruitful discussions of our common research and of open challenges we are facing when studying weather regimes on subseasonal timescales. More specifically, we advanced two main work packages: first, we will develop a year-round definition of East Asian weather regimes and verify their predictability in subseasonal numerical weather models, similarly to what we have already started for Euro-Atlantic weather regimes. Considering the strongly varying and thus fascinating climate of Japan, which ranges from heavy snow falls triggered by the mixing of cold Siberian air masses with humid maritime air masses from the Subtropics to devastating Typhoons that regularly hit the island, this research and our expertise in specific forecast products may ultimately help to improve operational subseasonal forecasting in Japan. In a second work package, we will draw upon the strong technical and statistical expertise of our colleagues at Tsukuba to verify the subseasonal predictability of year-round Euro-Atlantic weather regimes, which will be the foundation for many research goals of our group.
Since this was the first longer visit to Europe for some of our guests, we of course did not want to miss out on introducing them to some of the natural and culinary beauties of Southern Germany and to get to know each other better. We thus went for a hike in the Black Forest, visited Heidelberg, and ate delicious local food in various restaurants in Karlsruhe. In return, Mio, Akio and Takumi told us a lot about their certainly different but very interesting culture, about their traditions, and about the life as a scientist in their country. We are very excited to continue the joint research project and discuss our advances when some team members of the „Large-scale dynamics and predicitability group“ will visit the University of Tsukuba in fall 2019.
Junior Investigator Group "Large-scale Dynamics and Predictability": http://www.imk-tro.kit.edu/7425.php
Mio Matsueda’s group at University of Tsukuba: http://gpvjma.ccs.hpcc.jp/~mio/
Authors: Julian Quinting/Dominik Büeler