Media coverage: 6/21 NHK Sakidori and 6/22 NHK Ohayo Nippon

Our research on super-rapid severe weather prediction was covered by NHK TV program "Sakidori" (サキどり↑) on June 21, 2015, and by NHK TV morning news program "Ohayo Nippon" (おはよう日本) on June 22, 2015.

The NHK "Sakidori" TV crew came to the monthly research meeting with teleconference.
The crew also went to see the K computer.
The "Ohayo Nippon" reporter Mr. Akamatsu came to my office.
The covered contents are posted by the program webpages:


International Symposium on Data Assimilation 2015

International Symposium on Data Assimilation (ISDA) 2015 was held in RIKEN AICS, Kobe, Japan, on February 23-27, 2015. Total 116 participants include 42 from 10 countries overseas. The symposium was very successful with a lot of interesting talks and active discussions, thanks to all the participants!

The bottom photo includes local organizers from my team. Congratulations to Dr. Keiichi Kondo (front middle), who received the Best Poster Award! Ms. Yukie Komori (left) is greatly acknowledged for her dedicated work leading the symposium to a great success.
BTW, I should have posted this earlier!


Japan Geoscience Union Nishida Prize

It's been a while since the last post. A number of news happened, such as new team members, new research results and publications, and the big "International Symposium on Data Assimilation" in February, but I could not write posts here, which I would like to catch up sometime. Finally, I got motivated enough to share the news: the Japan Geoscience Union (JpGU) Nishida Prize.

On May 27, 2015, the first JpGU Nishida Prize was presented to 10 awardees at the Annual Meeting in Makuhari, Japan. The Prize recognizes mid-career scientists (up to 45 years old) with internationally-recognized outstanding research achievements. The photo, courtesy of Professor M. Satoh, includes three awardees in the field of atmospheric science, Professors Takemura (right) and Watanabe (second from right), and myself (left). Professor Nishida (second from right) was very kind to be in the photo. After the hard work on data assimilation, I would be very grateful for such a renowned recognition as one of the 10 first awardees of the broad geoscience fields.


Student intern

RIKEN AICS started a summer internship program in 2014. Our group accepted three internship students, Mr. Kitano from Hokkaido University (standing, middle), Mr. Kikuchi from Tohoku University (left), and Mr. Taniguchi from Hyogo Prefecture University (right). They joined us on August 29, 2014, and started working on short-term precipitation forecasts purely based on super-rapid 30-second observation data. Dr. Shigenori Otsuka, a researcher (sitting on the right), supervises their research activities. They all have different backgrounds, and I am very happy to see them discuss and help each other to tackle the tough problem. They have been making wonderful progress so far, with a lot of excitement and curiosity. I feel lucky to have this great opportunity to interact with those bright and enthusiastic young scientists.


10240-member ensemble Kalman filtering with an intermediate AGCM

We have achieved running a 3-week experiment of a 10240-member local ensemble transform Kalman filter (LETKF) with a simple low-resolution AGCM known as the SPEEDY model. The figure above shows 10240 equally-likely parallel earths, with magnified pictures. Every earth is slightly different, withing the range of uncertainties to the best of our knowledge.

The large ensemble data assimilation computations were only possible using the leading-edge K computer and the eigenvalue solver "EigenExa" that allows an extremely effective use of the K computer. We achieved amazingly high 44% efficiency, 263 TFLOPS using 4608 nodes of the K computer (about 1/20 of the full capacity). The parallel-efficient LETKF was also a must.

With 10240 members, we could obtain a very precise probabilistic representation of the earth atmosphere. Long-range error correlations beyond continental scales and bimodal structures of moisture variables were clearly represented. These were very difficult to observe with less than a few hundred members, a typical choice in ensemble data assimilation of the global atmosphere.

For more details, refer to the press release on this research achievement. Here are the links to the press release and the original research article published in Geophysical Research Letters.

  • Miyoshi, T., K. Kondo, and T. Imamura, 2014: The 10240-member ensemble Kalman filtering with an intermediate AGCM. Geophys. Res. Lett., 41, doi:10.1002/2014GL060863.


3rd RIKEN-Kyoto University Joint Workshop on Data Assimilation

The third workshop was held on Monday, July 28, 2014, in Kobe, following the first (blog) and the second. Four mathematicians and seven from my group on the application side discussed about mathematical problems on data assimilation. This time, my group provided several specific problems that we have been facing in our various application research.


Welcome lunch for Drs. Guo-Yuan Lien and Juan Ruiz

On Friday, July 11, 2014, we had a warm welcoming party for Drs. Guo-Yuan Lien (back row, fourth from left) and Juan Ruiz (front row, left most) over lunch in Kachoen. Our lab has been growing consistently by now, with eight full-time scientists and technical staff and three supporting staff in addition to five visiting scientists. Dr. Lien recently graduated from the University of Maryland, and his main focus was precipitation data assimilation in global numerical weather prediction. He will work on Big Data Assimilation (BDA) with the next-generation LES (large-eddy simulation) weather model SCALE. As for Dr. Ruiz, this is his third visit to Japan, and this time, he will stay for three months. He will also work on the BDA project with particular foci on the quality control of the Osaka/Kobe Phased Array Weather Radar and on parameter estimation methods in BDA applications.