A5045336533- Climate variability and models
- Meteorological Phenomena and Simulations
- Arctic and Antarctic ice dynamics
- Atmospheric and Environmental Gas Dynamics
- Tropical and Extratropical Cyclones Research
- Oceanographic and Atmospheric Processes
- Atmospheric Ozone and Climate
- Ionosphere and magnetosphere dynamics
- Climate change and permafrost
- Cryospheric studies and observations
- Geophysics and Gravity Measurements
- Methane Hydrates and Related Phenomena
- Atmospheric aerosols and clouds
- Solar and Space Plasma Dynamics
- Atmospheric chemistry and aerosols
- Fire effects on ecosystems
- Geology and Paleoclimatology Research
- earthquake and tectonic studies
- Ocean Waves and Remote Sensing
- Karst Systems and Hydrogeology
- Geological Studies and Exploration
- Multimedia Communication and Technology
- Urban and spatial planning
- Lung Cancer Treatments and Mutations
- stochastic dynamics and bifurcation
University of Tsukuba
2014-2023
Chuo University
2019-2023
Mitsubishi Heavy Industries (Germany)
2022
Naval Research Laboratory Information Technology Division
2016-2018
Kanagawa Institute of Technology
2014
Kawasaki Heavy Industries (Japan)
2011
Japan Agency for Marine-Earth Science and Technology
2005-2008
Institute for Global Environmental Strategies
2004-2006
NTT (Japan)
2005
University of Alaska Fairbanks
1989-2003
In this paper, we attempt to divide the global divergent field at upper troposphere in contributions from Hadley, Walker and monsoon circulations, using a monthly mean velocity potential 200-hPa level. First, zonal of is analysed represent Hadley circulation. The deviation then divided into its annual seasonal cycle parts, which are considered respectively. intensities each circulation measured by their peaks separated component. According separation, Walker, circulations appear be 120: 60:...
In this paper, we attempt to divide the global divergent field at upper troposphere in contributions from Hadley, Walker and monsoon circulations, using a monthly mean velocity potential 200-hPa level. First, zonal of is analysed represent Hadley circulation. The deviation then divided into its annual seasonal cycle parts, which are considered respectively. intensities each circulation measured by their peaks separated component. According separation, Walker, circulations appear be 120: 60:...
Abstract. This article presents new software for the analysis of global dynamical fields in (re)analyses, weather forecasts and climate models. A diagnostic tool, developed within MODES project, allows one to diagnose properties balanced inertio-gravity (IG) circulations across many scales. In particular, IG spectrum, which has only recently become observable, can be studied simultaneously mass wind while considering whole model depth contrast majority studies. The paper includes theory...
Abstract An extremely strong Arctic cyclone (AC) developed in August 2016. The AC exhibited a minimum sea level pressure (SLP) of 967.2 hPa and covered the entire Pacific sector Ocean on 16 August. At this time, was comparable to observed 2012, terms horizontal extent, position, intensity as measured by SLP. Two processes contributed explosive development AC: growth due baroclinic instability, similar extratropical cyclones, during early phase stage, later nonlinear via merging upper warm...
A statistical analysis was applied to Northern Hemisphere land surface temperatures (1850–2018) try identify the main drivers of observed warming since mid-19th century. Two different temperature estimates were considered—a rural and urban blend (that matches almost exactly with most current estimates) a rural-only estimate. The indicates long-term 0.89 °C/century 1850, while 0.55 °C/century. This contradicts common assumption that thermometer-based global indices are relatively unaffected...
In this study, intensities and trends of Hadley, Walker, monsoon circulations are compared for the IPCC 20th Century simulations 21st simulations, using upper tropospheric velocity potential data. As a result, we showed significantly weaker biases in Walker JJA climate simulations. The dispersal scatter diagram model is considerably large. same analyses applied to investigate these tropical response projected global warming. it anticipated that weakened by 9, 8, 14%, respectively, late...
A stable isotope dilution method is described that allows measurement of cholic acid (CA) kinetics, is, pool size, fractional turnover rate (FTR), and synthesis in mice, rats, humans. Decay administered [2,2,4,4-2H4]CA enrichment was measured time 50-μl plasma samples by gas-liquid chromatography/electron capture negative chemical ionization-mass spectrometry, applying the pentafluorobenzyl-trimethylsilyl derivative. The kinetic data expressed species-dependent differences. CA sizes were...
A diagnostic energetics scheme is developed in order to investigate the energy flows among three-dimensional normal modes (Hough horizontal) atmosphere. This applied GFDL version of FGGE level IIIb data during winter from December 1978 February 1979.The resultant flow summarized as follows: available potential generated at zonal baroclinic (especially vertical mode m=4) directly converted into kinetic planetary scale barotropic mode. Kinetic cyclone transformed and eddy energies...
A global energetics analysis is presented for the FGGE SOP-1 and SOP-2 with ECMWF GFDL data sets. Both integral properties spectral characteristics are examined. There a large discrepancy between present previously available estimates concerning level of potential energy kinetic energy. This attributable to an earlier restriction coverage. significant seasonal difference in reservoir Northern Hemisphere, whereas diference minor Southern Hemisphere. leads contrast globally integrated budget...
Abstract The drought climate of Japan from 1902 to 2009 was analyzed using an effective index (EDI). Drought regions were identified by hierarchical cluster analysis characteristics (duration, severity, and onset end dates) obtained 50 observation stations. results indicated that droughts could be divided into four groups (G1–G4) reflected the local climate. related precipitation as follows. summer rainy season affected G2–G4, in which occurred mainly during spring relieved before after...
In this study, a volcanic ash tracking model called "PUFF" is applied to the actual eruption of Usu volcano on 31 March 2000 in order infer movement airborne clouds for aviation safety. The PUFF was developed and operated by Alaska Volcano Observatory since Redoubt 1989. performance examined study based ground truth observed distribution tephra ground. According simulation, plume erupted from first moved eastward New Chitose International Airport. As upper air westerly wind gradually shifted...
Abstract Arctic cyclones (ACs) are a severe atmospheric phenomenon that affects the environment. This study assesses forecast skill of five leading operational medium‐range ensemble forecasts for 10 extraordinary ACs occurred in summer during 2008–2016. Average existence probability predicted was >0.9 at lead times ≤3.5 days. central position error less than half mean radius (469.1 km) 2.5–4.5 pressure 5.5–10.7 hPa such times. Therefore, prediction systems generally predict within 469.1...
Three-dimensional normal mode functions are applied to the analysis of energetics general circulation during FGGE year. The GFDL data used for computation both and standard spectral energetics. global presented in a barotropic baroclinic decomposition zonal mean eddy energies stationary transient components flow. energy generated component is first transformed through process atmospheric instability. It then further by nonlinear up-scale cascade kinetic energy. thus maintains its structure...
This paper presents a novel generalized computational framework for quantitative kinematic evaluation of movement in rehabilitation clinic setting. The integrates clinical knowledge and data‐driven analysis together systematic manner. provides three key benefits to rehabilitation: (a) the resulting continuous normalized measure allows clinician monitor quality on fine scale easily compare impairments across participants, (b) reveals effect individual components composite performance helping...
In order to evaluate airborne ash densities, a real-time volcanic dispersion model, PUFF, is applied the February 13, 2014 eruption of Kelud volcano in Indonesia. The emission rate mass from vent estimated based on empirical formulae tested at Sakurajima using ground deformation and seismic monitoring data. According result PUFF model simulation, circular shape anvil cloud 17 km height extends during first two hours over radius 200 volcano. core region within 50 shows an density 1000 mg/m 3...
In this study, a real-time volcanic ash dispersion model called PUFF is applied to the Sakura-jima volcano erupted on 16 June 2018 assess performance of new system connected with emission rate estimation. The mass from vent estimated based an empirical formula developed for using seismic monitoring and ground deformation data. According time series rate, major eruption occurred at 7:20 JST indicating 1000 t/min continued 15 min showing plume height 4500 m. It observed that we need introduce...
In this study, characteristics of the energy spectrum in zonal wavenumber domain are examined for cloud resolving global model NICAM. A series numerical experiments conducted NICAM with various horizontal resolutions from 224 km (glevel-5) to 7.0 (glevel-10) using T2K-Tsukuba System and 3.5 (glevel-11) Earth Simulator (ES). The spectra most obey k-3 power law synoptic sub-synoptic scales (wavenumbers k = 5 30). However, slope glevel-5 becomes much steeper around 10. Nastrom et al. (1985)...
In this study, baroclinic instability of the northern winter atmosphere is investigated in context dynamical interpretation Arctic oscillation. The unstable solutions, obtained by a method 3D normal mode expansion, are compared for observed zonal basic states with strong and weak polar vortices reference to oscillation index. As result eigenvalue problem linear stability analysis, characteristic solution that dominates high latitudes when vortex strong. called monopole Charney M1, which...
Abstract In this study, we carried out a quantitative heat budget analysis of the polar troposphere in and around Alaska for winter 1988/89. The was characterized by drastic temperature variations. surface minimum temperatures interior were lower than −40°C during two weeks late January. This cold period followed extremely warm weather February, especially northern Alaska. results three-month average (December to February) show that energy continental air mass is maintained balance...
In this study, Multi-Center Grand Ensembles (MCGEs) were constructed by combining five operational medium-range ensemble forecasts: CMC, ECMWF, JMA, NCEP, and UKMO with equal weights no bias correction. The forecast performance of the MCGEs relative to ECMWF ensemble, having best in world, was investigated using seasonal Root Mean Square Error (RMSE) Ranked Probability Score (RPS) for 500 hPa geopotential height over Northern Hemisphere (20°N-90°N) from December 2006 November 2007.It found...