SAKAI Tetsu

Job title	Head / The 2nd Lab. / Department of Observation and Data Assimilation Research
E-mail
Personal	Researchmap ORCID Web of Science
Expertise	Lidar (Raman, DIAL and Mie/Rayleigh) for measuring water vapor, aerosol, cloud, and ozone
Degree	Doctor of Science, Nagoya University
Project	Development of advanced water vapor observation systems via integration of ground-based remote sensing technology and other techniques
Awards	Director's Award to Mechanism Elucidation Research Group of Stationary Linear Mesoscale Convective Systems, Meteorological Research Institute (group award) (2023) NASA Group Achievement awards for the CAMP2Ex campaign (group award) (2020) The Society of Instrument and Control Engineers Award for Creative Work (2006)
Memberships on Committee	Core Member of WMO SC-MINT Expert Team on Upper Air Measurements (ET-UAM) Board Member of Laser Radar Society of Japan (LRSJ) and project research committee on satellite-borne lidar Board Member of International Coordination-group for Laser Atmospheric Studies (ICLAS)
Publications	Sakai, T., O. Uchino, T. Nagai, B. Liley, R. Querel, I. Morino, Y. Jin, T. Fujimoto, E. Oikawa, N. Oshima, 2025: Stratospheric aerosol backscatter and depolarization ratio observed with ground-based lidar at Tsukuba, Japan, and Lauder, New Zealand. J. Geophysical Research: Atmosphere, 130, e2024JD041329. Inoue, J., H. Seko, K. Sato, and T. Sakai, 2025: Operational capability of drone-based meteorological profiling in an urban area. J. Geophysical Research: Atmosphere, 130, e2024JD041927. Asher, E., A. Baron, P. Yu, M. Todt, P. Smale, B. Liley, R. Querel, T. Sakai, I. Morino, Y. Jin, T. Nagai, O. Uchino, E. Hall, P. Cullis, B. Johnson, T.D. Thornberry, 2024: Balloon baseline stratospheric aerosol profiles (B2SAP)—Perturbations in the southern hemisphere, 2019-2022. J. Geophysical Research: Atmosphere, 129, e2024JD041581. Yoshida, S., T. Sakai, T. Nagai, Y. Ikuta, T. Kato, K. Shiraishi, R. Kato, and H. Seko, 2024: Water vapor lidar observation and data assimilation for a moist low-level jet triggering a mesoscale convective system. Mon. Wea. Rev., 152, 1119–1137. Khaykin, S., G. Taha, T. Leblanc, T. Sakai, I. Morino, B. Liley, and S. Godin-Beekmann , 2024: Stratospheric aerosols [in “State of the Climate in 2023”]. Bull. Amer. Meteor. Soc., 105(8), S96–S98. Hofer, J., Seifert, P., Liley, J. B., Radenz, M., Uchino, O., Morino, I., Sakai, T., Nagai, T., and Ansmann, A., 2024: Aerosol-related effects on the occurrence of heterogeneous ice formation over Lauder, New Zealand∕Aotearoa, Atmos. Chem. Phys., 24, 1265–1280. Sakai, T., Yoshida, S., Nagai, T., Ikuta, Y., Shoji, Y., 2023: Comparison of lower tropospheric water vapor vertical distribution measured with Raman lidar and DIAL and the impact of data assimilation in numerical weather prediction model. In: Sullivan, J.T., et al. Proceedings of the 30th International Laser Radar Conference. ILRC 2022. Springer Atmospheric Sciences. T. T. Ngoc Trieu, I. Morino, O. Uchino, Y. Tsutsumi, T. Izumi, T. Sakai, T. Shibata, H. Ohyama, T. Nagahama, 2023: Long-range transport of CO and aerosols from Siberian biomass burning over northern Japan during 18–20 May 2016, Environmental Pollution, 32, 12119. Yoshida, S., T. Sakai, T. Nagai, Y. Ikuta, Y. Shoji, H. Seko, and K. Shiraishi, 2022: Lidar observations and data assimilation of low-level moist inflows causing severe local rainfall associated with a mesoscale convective system. Mon. Wea. Rev., 150,1781-1798. Khaykin, S., A. Podglajen, F. Ploeger, J. Grooß, F. Tence, S. Bekki, K. Khlopenkov, K. Bedka, L. Rieger, A. Baron, S. Beekmann, B. Legras, P. Sellitto, T. Sakai, J. Barnes, O. Uchino, I. Morino, T. Nagai, R. Wing, G. Baumgarten, M. Gerding, V. Duflot, G. Payen, J. Jumelet, R. Querel, B., A. Bourassa, B. Clouser, A. Feofilov, A. Hauchecorne, and F. Ravetta, 2022: Global perturbation of stratospheric water and aerosol burden by Hunga eruption, Commun Earth Environ,3, 316. Tran Thi Ngoc Trieu, I. Morino, O. Uchino, Y. Tsutsumi, T. Sakai, T. Nagai, A. Yamazaki, H. Okumura, K. Arai, K. Shiomi, D. F. Pollard, and B. Liley , 2022: Influences of aerosols and thin cirrus clouds on GOSAT XCO2 and XCH4 using Total Carbon Column Observing Network, sky radiometer, and lidar data. Int. J. Remote Sensing, 43:5, 1770-1799. Huang, Y., J. Kok, K. Kandler, H. Lindqvist, T. Nousiainen, T. Sakai, A. Adebiyi, O. Jokinen, 2020: Climate models and remote sensing retrievals neglect substantial desert dust asphericity. Geophys. Res. Lett., 47, e2019GL086592. Sakai, T., S. Yoshida, T. Nagai, and Y. Shoji, 2020: Development of water vapor lidar and observational studies for heavy rain prediction. The Review of Laser Engineering, 48, 595-598 (in Japanese). Yoshida, S., S. Yokota, H. Seko, T. Sakai, T. Nagai, 2020: Observation System Simulation Experiments of Water Vapor Profiles Observed by Raman Lidar using LETKF System. SOLA, 16, 43-50. Sakai, T., Nagai, T., Izumi, T., Yoshida, S., and Shoji, Y., 2019: Automated compact mobile Raman lidar for water vapor measurement: instrument description and validation by comparison with radiosonde, GNSS, and high-resolution objective analysis. Atmos. Meas. Tech., 12, 313-326. Bagtasa, G., M. G. Cayetano, C-S. Yuan, O. Uchino, T. Sakai, T. Izumi, I. Morino, T. Nagai, R. C. Macatangay, V. A. Velazco, 2019: ALong-range transport of aerosols from East and Southeast Asia to northern Philippines and its direct radiative forcing effect. Atmos. Environ., 218, 11707. Velazco, V.A., I. Morino, O. Uchino, A. Hori, M. Kiel, B. Bukosa, N.M. Deutscher, T. Sakai, T. Nagai, G. Bagtasa, T. Izumi, Y. Yoshida, D.W.T. Griffith, 2017: TCCON Philippines: First measurement results, satellite data and model comparisons in Southeast Asia. Remote Sensing, 9, 1228. Uchino, O., Sakai, T., Izumi, T., Nagai, T., Morino, I., Yamazaki, A., Deushi, M., Yumimoto, K., Maki, T., Tanaka, T. Y., Akaho, T., Okumura, H., Arai, K., Nakatsuru, T., Matsunaga, T., and Yokota, T., 2017: Lidar detection of high concentrations of ozone and aerosol transported from northeastern Asia over Saga, Japan. Atmospheric Chemistry and Physics, 17,1865-1879. Sakai, T., O. Uchino, T. Nagai, B. Liley, I. Morino, and T. Fujimoto, 2016: Long-term variation of stratospheric aerosols observed with lidars over Tsukuba, Japan, from 1982 and Lauder, New Zealand, from 1992 to 2015. Journal of Geophysical Research-Atmosphere, 121,110283-10293. Walker, M., D. Venable, D. N. Whiteman, T. Sakai, 2016: Application of the lamp mapping technique for overlap function for Raman lidar systems. Applied Optics, 55,2551-2558. Ohyama, H., S. Kawakami, T. Tanaka, I. Morino, O. Uchino, M. Inoue, T. Sakai, T. Nagai, A. Yamazaki, A. Uchiyama, T. Fukamachi, M. Sakashita, T. Kawasaki, T. Akaho, K. Arai, and H. Okumura, 2015: Observations of XCO2 and XCH4 with ground-based high-resolution FTS at Saga, Japan, and comparisons with GOSAT products. Atmospheric Measurement Techniques, 8, 5263-5276. Jin, Y., K. Kai, K. Kawai, T. Nagai, T. Sakai, A. Yamazaki, A. Uchiyama, D. Batdorj, N. Sugimoto, T. Nishizawa, 2015: Ceilometer calibration for retrieval of aerosol optical properties. Journal of Quantitative Spectroscopy and Radiative Transfer, 153, 49-56. Sakai, T., O. Uchino, I. Morino, T. Nagai, T. Akaho, T. Kawasakai, H. Okumura, K. Arai, A. Uchiyama, A. Yamazaki, T. Matsunaga, T. Yokota, 2014: Vertical distribution and optical properties of volcanic ash from Mt. Sakurajima detected with lidar and skyradiometer over Saga. Journal of The Remote Sensing Society of Japan, 34, 197-204. Ridley, D. A, S. Solomon, J. E. Barnes, V. D. Burlakov, T. Deshler, S. I. Dolgii, A. B. Herber, T. Nagai, R. R. Neely III, A.V. Nevzorov, C. Ritter, T. Sakai, B. D. Santer, M. Sato, A. Schmidt, O. Uchino and J. P. Vernier, 2014: Total volcanic stratospheric aerosol optical depths and implications for global climate change. Geophysical Research Letters, 41, 7763–7769. /doi:doi:10.1002/2014GL061541 Sakai, T., N. Orikasa, T. Nagai, M. Murakami, T. Tajiri, A. Saito, K. Yamashita, and A. Hashimoto, 2014: Balloon-borne and Raman lidar observations of Asian dust and cirrus cloud properties over Tsukuba, Japan. Journal of the Geophysical Research - Atmosphere, 119, 3295–3308. /doi:doi:10.1002/2013JD020987
Project	Research on Data Assimilation Technology and High-level Use of Observation Data KAKENHI "Development and experimental validation of shipborne water vapor and wind lidar for early detection of heavy rain"