投稿者「TaylorJames」のアーカイブ

Data Assimilation Seminar – Dr Naoto Nakano

We held the 64th Data Assimilation Seminar at RIKEN Center for Computational Science (R-CCS) on 25 October.

The talk was given by Dr Naoto Nakano who is a senior lecturer in the Department of Mathematics at Kyoto University. Today he spoke about his work in data driven modelling based on reservoir dynamics. This included work using the 1963 and 1996 lorenz model to try to better predict the state of variables using pre-exisiting timeseries.

We would like to thank Dr Nakano very much for visiting us again in Kobe and look forward to his next visit!

For more information about this and all our DA seminars at RIKEN R-CCS, please see the DA seminar page:

http://www.data-assimilation.riken.jp/en/events/da_seminar/index.html

Data Assimilation Seminar – Professor Michael Ng

We held the 63rd Data Assimilation Seminar at RIKEN Center for Computational Science (R-CCS) on 30 September.

The talk was given by Professor Michael Ng from Hong Kong University who spoke about his work on robust tensor completion using single value decompression . He demonstrated how these methods can be applied to solve many different problems, including image processing. We would like to thank Professor Ng for given his talk and meeting with the team during his stay. We hope that he will visit us again very soon and update us with his research progress.

For more information about this and all our DA seminars at RIKEN R-CCS, please see the DA seminar page:

http://www.data-assimilation.riken.jp/en/events/da_seminar/index.html

tensors

Data Assimilation Seminar – Professor Shu-Chih Yang

We held the 62nd Data Assimilation Seminar at RIKEN Center for Computational Science (R-CCS) on 10 September August.

The talk was given by Professor Shu-Chih Yang from National Central University in Taiwan who has been visiting the data assimilation team for collaborative research. She discussed her work with high-impact weather prediction in Taiwan and her recent developments for predicting heavy precipitation weather events and air pollution. This included the development of the WRF-Local Ensemble Transform Kalman Filter radar data assimilation system (WLRAS), which has undergone improvements recently to reduce sampling errors, assimilate fast moisture information and implementation of a dual-localization scheme.

We would like to thank Professor Yang for visiting us again in Kobe and presenting her recent research.

For more information about this and all our DA seminars at RIKEN R-CCS, please see the DA seminar page:

http://www.data-assimilation.riken.jp/en/events/da_seminar/index.html

Data Assimilation Seminar – Dr. Shigenori Otsuka [R-CCS]

We held the 61st Data Assimilation Seminar at RIKEN Center for Computational Science (R-CCS) on 21 August.

The talk was given by Dr. Shigenori Otsuka from the Data Assimilation team here at RIKEN. He presented his research using two optical-flow based nowcasting systems for improving short-range precipitation prediction, 1) Phased Array Weather Radar (PAWR) 3D nowcasting system and 2) Global Satellite Mapping of Precipitation (GSMaP) RIKEN Nowcast (RNC) system. Given the limitations of using optical-flow systems for weather prediction, one being that convective weather systems can evolve very rapidly and non-linearly, his research has steered towards the use of deep learning techniques, where he has applied the Convolutional Long Short-Term Memory (Conv-LSTM) algorithm to the PAWR data. Preliminary results of real-time experiments with Conv-LSTM showed improvements in short-range forecasts.

We would like to thank Dr Otsuka for his interesting talk and wish him well with his continuing research using nowcasting systems.

For more information about this and all our DA seminars at RIKEN R-CCS, please see the DA seminar page:

http://www.data-assimilation.riken.jp/en/events/da_seminar/index.html

Data Assimilation Seminar – Professor Serge Guillas [UCL]

We held the 59th Data Assimilation Seminar at RIKEN Center for Computational Science (R-CCS) on 31 May.

The talk was given by Professor Serge Guillas who was visiting us from University College London (UCL). Professor Guillas spoke about current solutions to investigating uncertainties in tsunami impacts, including investigating the potential for landslides as a source of tsunamis in the Western Indian Ocean and the risk of tsunamis from the Makran subduction zone. Part of his research was using very high resolution models to simulate potential tsunamis in these regions and predict seabed deformations and landslide velocities. We wish Professor Guillas well in the future with his research on this very important topic and hope that he will return again soon to R-CCS to update us on his progress. Thank you!

For more information about this and all our DA seminars at RIKEN R-CCS, please see the DA seminar page:

http://www.data-assimilation.riken.jp/en/events/da_seminar/index.html

Data Assimilation Seminar – Prof. Ming-Cheng Shiue [NCTU]

We held the 58th Data Assimilation Seminar at RIKEN Center for Computational Science (R-CCS) on 7 May.

The seminar was given by Professor Ming-Cheng Shiue from the National Chiao Tung University, Taiwan. He spoke about his research on hybrid, nonlinear continuous data assimilation algorithms for Lorenz systems. He presented his work showing that approximate solutions converge to reference solutions over time provided that only first and second variables of Lorenz systems are synchronized. He also presented research on two continuous and discrete DA algorithms for 2D Navier-Stokes equations, showing how present and past observations at each time step provide a way that new methods could outperform old ones.

We are very grateful to Professor Shiue for visiting us at RIKEN and hope to see him again soon.

For more information about this and all our DA seminars at RIKEN R-CCS, please see the DA seminar page:

http://www.data-assimilation.riken.jp/en/events/da_seminar/index.html

Data Assimilation Seminar – Dr Atsushi Okazaki [R-CCS]

We held the 57th Data Assimilation Seminar at RIKEN Center for Computational Science (R-CCS) on 25 April.

The talk was given by our very own Dr. Atsushi Okazaki from the Data Assimilation team at RIKEN R-CCS. Dr Okazaki presented his research on testing the feasibility of a a new type of geostationary satellite that would be able to provide continuous space borne precipitation radar observations, similar to those of Tropical Rainfall Measuring Mission (TRMM) and Global Precipitation Measurement (GPM). Dr. Okazaki has been testing the impact of such observation on numerical weather prediction for a tropical cyclone case. His results showed promising impact on track and intensity forecasts with the assimilation of such observations.

Dr Okazaki has been member of the Data Assimilation team for 3 years but will leave next month to start a new position in the United States . We are very sad to see him leave but wish him all the best in the future and hopefully see him again very soon. Good luck Atsushi!

For more information about this and all our DA seminars at RIKEN R-CCS, please see the DA seminar page:

http://www.data-assimilation.riken.jp/en/events/da_seminar/index.html

Data Assimilation Seminar – Dr. Tie Dai [LASG]

We held the 56th Data Assimilation Seminar at RIKEN Center for Computational Science (R-CCS) on 1 February.

The talk was given by Dr. Tie Dai from State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG), Institute of Atmospheric Physics at the Chinese Academy of Sciences.

Dr Dai talked about his work developing an aerosol data assimilation system based on the NICAM model and LETKF. He showed how he has been able to successfully assimilate observations from both the MODIS satellite and Himawari 8 satellite to produce an aerosol analysis for the improvement of short-range aerosol forecasting over Eastern Asia.

We would like to thank Dr Dai very much for visiting us here in Kobe and for the lively discussion about his work! We wish him well with his research in the future.

For more information about this and all our DA seminars at RIKEN R-CCS, please see the DA seminar page:

http://www.data-assimilation.riken.jp/en/events/da_seminar/index.html

Data Assimilation Seminar – Dr Alison Fowler/Ms. Jemima Tabeart [U Reading UK]

We held the 54th and 55th Data Assimilation Seminars at RIKEN Center for Computational Science (R-CCS) on January 28.

The first talk was given by Dr. Alison Fowler from the University of Reading (UK), who spoke about observation error correlations and how we might apply data compression techniques that retain maximum information content of the observations, allowing us to use more observations in our data assimilation.

The second talk was given by Jemima Tabeart, also from the University of Reading. She spoke about available reconditioning methods that can be used to improve the condition number of correlated matrices. She found that she could improve the convergence by introducing correlated observation error covariance matrices with only small changes to retrieved variables.

We would like to thank Alison and Jemima for visiting us here at RIKEN R-CCS and giving two very interesting talks on observation error covariance matrix estimation – a very important topic in this era of Big Data!  

For details, please see the following DA seminar page:

http://www.data-assimilation.riken.jp/en/events/da_seminar/index.html

53rd DA Seminar – Dr Eugenia Kalnay

We held the 53rd Data Assimilation Seminar at RIKEN Center for Computational Science (R-CCS) on January 18. The seminar talk was given by Dr Eugenia Kalnay from the University of Maryland.

Dr Kalnay spoke about how wind and solar farms may lead to unintended climate changes caused by changes to land surface properties. She showed using a climate model how a large scale installation of wind and solar farms across the Sahara would lead to a local temperature increase and precipitation increase, which could have a positive impact on vegetation.

We would like to thank Dr Kalnay very much for visiting us again in Kobe and for the many great discussions we had with her during her stay. We look forward to welcoming her again to R-CCS soon!