A5086723322- Tropical and Extratropical Cyclones Research
- Meteorological Phenomena and Simulations
- Climate variability and models
- Ocean Waves and Remote Sensing
- Geophysics and Gravity Measurements
- Geological and Geophysical Studies
- Oceanographic and Atmospheric Processes
- Electrohydrodynamics and Fluid Dynamics
- Aerosol Filtration and Electrostatic Precipitation
- earthquake and tectonic studies
- Plant Surface Properties and Treatments
- Precipitation Measurement and Analysis
- Earthquake Detection and Analysis
- Insect-Plant Interactions and Control
- High-pressure geophysics and materials
- Sesame and Sesamin Research
- Atmospheric and Environmental Gas Dynamics
- Cassava research and cyanide
- Solar and Space Plasma Dynamics
- Atmospheric chemistry and aerosols
- Seismology and Earthquake Studies
- Rice Cultivation and Yield Improvement
- Geological and Geochemical Analysis
- Flood Risk Assessment and Management
- Remote-Sensing Image Classification
Kyoto University
2009-2025
Yokohama National University
2022-2025
University of the Ryukyus
2015-2023
Prevention Institute
2023
Meteorological Research Institute
2013-2021
Japan Meteorological Agency
2013-2021
Aichi Prefectural University
2021
University of the Ryukyus University Hospital
2014-2020
National Taiwan University
2010-2019
Sun Yat-sen University
2019
This study statistically investigates the characteristics of tropical cyclones (TCs) undergoing rapid intensification (RI) in western North Pacific 37 years from 1979 to 2015 and relevant atmospheric oceanic environments. Among 900 TCs, 201 TCs RI (RI-TCs) are detected by our definition as a wind speed increase 30 kt (15.4 m s −1 ) or more 24-h period. RI-TCs potentially occur throughout year, with low variation RI-TC occurrence rate among seasons. Conversely, annual varies widely. In El...
Observations of tropical cyclones (TC) from aircraft and in situ platforms provide critical unique information for analyzing forecasting TC intensity, structure, track, their associated hazards. This report, prepared the tenth International Workshop on Tropical Cyclones (IWTC-10), discusses data collected around world TCs over past four years since IWTC-9, improvements to observing techniques, new instruments designed achieve sustained targeted atmospheric oceanic observations, select...
Journal Article Studies on the Life History of Pineapple Mealybug, Pseudococcus brevipes (Ckll.) Get access K. Ito Experiment Station, University Hawaii, Honolulu Search for other works by this author on: Oxford Academic PubMed Google Scholar Economic Entomology, Volume 31, Issue 2, 1 April 1938, Pages 291–298, https://doi.org/10.1093/jee/31.2.291 Published: 01 1938
Abstract This work quantifies the benefits of using a high-resolution atmosphere–ocean coupled model in tropical cyclone (TC) intensity forecasts vicinity Japan. To do so, large number calculations were performed by running Japan Meteorological Agency (JMA) nonhydrostatic atmospheric mesoscale (AMSM) and (CMSM). A total 281 3-day compiled for 34 TCs from April 2009 to September 2012 each model. The performance these models is compared with JMA global spectral (GSM) that used operational TC...
Abstract In this report, we propose a deep learning technique for high-accuracy estimation of the intensity class typhoon from single satellite image, by incorporating meteorological domain knowledge. By using Visual Geometric Group’s model, VGG-16, with images preprocessed fisheye distortion, which enhances typhoon’s eye, eyewall, and cloud distribution, achieved much higher classification accuracy than that previous study, even sequential-split validation. Through comparison t-distributed...
This study statistically investigates the characteristics of tropical cyclones (TCs) undergoing rapid intensification (RI) in Southwest Pacific (SWP) region 37 years from 1986 to 2022. Among 364 TCs, 82 rapidly intensifying TCs (RI-TCs) were defined as that experienced maximum wind speed increase 30 kt (15.4 m s−1) or more a 24-h period. RI-TCs are frequently observed over zonally elongated area around coral sea, south Solomon Islands (Solomon Sea), Vanuatu, Fiji, Tuvalu, Tokelau and Samoa,...
Data assimilation is a technique that optimizes the parameters used in numerical model with constraint of dynamics achieving better fit to observations. Optimized can be utilized for subsequent prediction and predicted physical variables are presumably closer observations will available future, at least, comparing those obtained without optimization through data assimilation. In this work, an adjoint system developed optimizing relatively large number spatially inhomogeneous frictional...
The inner core of Tropical Cyclone Lan was observed on 21-22 October 2017 by GPS dropsondes during the first aircraft missions Cyclones-Pacific Asian Research Campaign for Improvement Intensity Estimations/Forecasts (T-PARCII). To evaluate impact forecast skill, 12 36-h forecasts were conducted using a Japan Meteorological Agency non-hydrostatic model (JMA-NHM) with JMA-NHM-based mesoscale four-dimensional data assimilation (DA) system. Track skill improved over all times dropsonde data....
Tropical cyclone (TC) intensity forecasts issued by the Regional Specialized Meteorological Centre (RSMC) Tokyo - Typhoon Center are systematically compiled to analyze long-term behavior of errors and explore potential for improvement in forecast accuracy using a statistical correction approach. In this study, dataset is constructed from annual statistics every single listed on reports activities RSMC Tokyo. This study found that (1) mean has not improved over 26 years (2) tend be larger...
Abstract Recent idealized simulations have shown that a system of binary tropical cyclones (TCs) induces vertical wind shear (VWS) in each TC, which can subsequently modify the tracks these TCs through asymmetric diabatic heating. This study investigates three-dimensional effects western North Pacific using best track and ERA5 reanalysis data. The TC motion was found to deviate systematically from steering flow. direction deviation is clockwise repelling with respect midpoint separation...
Afterslip sometimes triggers subsequent earthquakes within a timescale of days to several years. Thus, it may be possible predict the occurrence such triggered earthquake by simulating spatio-temporal evolution afterslip with estimated frictional parameters. To demonstrate feasibility this idea, we consider plate interface model where propagates between two asperities following rate-and-state friction law, and adopt an adjoint data assimilation method optimize Synthetic observation are...
While the fundamental understanding of tropical cyclone (TC) movement is fairly mature, notable advancements are still being made.This paper summarizes new concepts and updates to existing theories on TC obtained from simplified barotropic models, full-physics data analysis, particularly since 2014.The scope includes recent works interaction between a its environment, predictability related movement.Although conventional steering flow, β-gyre, diabatic heating remain important, more complete...
Abstract This study examines the diurnal variation of convective area and eye size 30 rapidly intensifying tropical cyclones (RI TCs) that occurred in western North Pacific from 2015 to 2017 utilizing Himawari-8 satellite imagery. The can be divided into active (ACA), mixed phase, inactive (IACA) based on specific thresholds brightness temperature. In general, ACA tends develop vigorously late afternoon early next morning, while phase IACA during day. pattern indicates potential for evolve...
Abstract This study hypothesises that the motion of binary tropical cyclones (TCs) can be modified by diabatic heating (DH) asymmetry associated with self‐induced vertical wind shear. To demonstrate this hypothesis in quiescent environment, a set idealised f ‐plane numerical experiments such as identical (varied initial separation distance) and non‐identical TC intensity size) are conducted. Results show tracks affected distance, size, is, influence radius. Identical critical distance for...
Abstract A new sensitivity analysis method is proposed for the ensemble prediction system in which a tropical cyclone (TC) position taken as metric. Sensitivity defined slope of linear regression (or its approximation) between state variable and scalar representing TC based on simulation. The experiment results illustrate important regions track forecast. typhoon-position-oriented (TyPOS) applied to Typhoon Shanshan (2006) verification time up 48 h. field central latitude with respect...
Upper-tropospheric aircraft reconnaissance was carried out for Typhoon Lan (2017) using a civil jet with newly developed dropsonde system. This the first time Japanese research group observed inner core of an intense typhoon dropsondes. paper describes warm-core structure in eye and associated thermodynamic kinematic features eyewall. During two days reconnaissance, preserved its peak intensity environment strengthening vertical shear. The dropsondes captured double higher perturbation...
Abstract An ensemble Kalman filter (EnKF) that uses a regional mesoscale atmosphere–ocean coupled model was preliminarily examined to provide realistic sea surface temperature (SST) estimates and represent the uncertainties of SST in data assimilation strategies. The system evaluated through cycle experiments over one-month period from July August 2014, during which time tropical cyclone (TC) as well severe rainfall events occurred. results showed with reproduced distributions realistically...
Abstract The sporadic formation of short-lived convective clouds in the eye Tropical Cyclone (TC) Trami (2018) is investigated using dropsonde data and simulation results from a coupled atmosphere–ocean model. According to satellite data, top height exceeds 9 km above mean sea level, considerably taller than that typical hub (2–3 km). These are located 10–30 away TC center. Hence, these called deep (DECs) this study. reveal an increase relative humidity region during DECs. Short-lived...
Abstract This work investigates the rapid weakening (RW) processes of Typhoon Trami (2018) by examining sea surface temperature (SST) cooling based on air–sea coupled simulations during typhoon passage. The cold wake and Trami’s RW occurred as storm was moving at a very slow translation speed. A marked structural change is found in three-dimensional ocean-coupled model experiment stage, which convective clouds bursts inner core simulated TC dramatically decrease, resulting loss diabatic...
Abstract: We investigated the pre‐ovipositional period of Nilaparvata lugens originating from tropical, subtropical and temperate regions East Southeast Asia using laboratory experiments to compare migration capability populations. Macropter females collected in 1992 Japan North Vietnam had a longer immature than those tropical Indochina Peninsula, i.e. day first oviposition after eclosion was about 3 days later former Populations 1993 1994 Japan, Central South China, also that Malaysian...
Currently, the Regional Specialized Meteorological Center Tokyo applies satellite-based Dvorak technique using relationship developed by Koba et al. (1990) for one of important sources tropical cyclone (TC) intensity analysis. To improve TC analysis, we revisited Koba's used estimating minimum sea level pressure (MSLP) considering case selection, aircraft data treatment, current (CI) numbers, and additional explanatory variables. The root mean squared difference (RMSD) MSLP between...
Abstract To clarify the effect of fluctuations in surface stress and heat fluxes on intensity a mature-state hurricane, sensitivity analysis is performed by using cloud-permitting nonhydrostatic axisymmetric adjoint model. The response function our experiment tangential velocity at top boundary layer eyewall. As result an integration backward to 4 min prior specified time, dipole pattern appears fields with respect vertical velocity, potential temperature, mixing ratio water vapor. A...
One of the remarkable environmental characteristics tropical cyclone (TC) Hagibis (2019) was positive sea surface temperature (SST) anomaly observed in western North Pacific Ocean. In this study, an ensemble-based sensitivity experiment conducted with a nonhydrostatic model, focusing on impact SST TC motion. The analyzed (warm run) moved faster near mainland Japan than lowered (cold run), as warm run embedded earlier mid-latitude westerly jet located to north that cold run. displacement...