A5002863593- Oceanographic and Atmospheric Processes
- Climate variability and models
- Methane Hydrates and Related Phenomena
- Arctic and Antarctic ice dynamics
- Meteorological Phenomena and Simulations
- Geological Studies and Exploration
- Tropical and Extratropical Cyclones Research
- Geology and Paleoclimatology Research
- Marine and environmental studies
- Ocean Waves and Remote Sensing
- Food Industry and Aquatic Biology
- Geochemistry and Geologic Mapping
- Atmospheric and Environmental Gas Dynamics
- Hydrocarbon exploration and reservoir analysis
- Aquatic and Environmental Studies
- Marine and fisheries research
- Historical and Environmental Studies
- Arctic and Russian Policy Studies
- Ionosphere and magnetosphere dynamics
- Planetary Science and Exploration
- Constructed Wetlands for Wastewater Treatment
- Marine and coastal ecosystems
- Atmospheric Ozone and Climate
- Geological and Geophysical Studies
- Maritime Navigation and Safety
The University of Tokyo
2021-2023
Sphere Institute
2023
B. Verkin Institute for Low Temperature Physics and Engineering of the National Academy of Sciences of Ukraine
2017-2020
Hokkaido University
2018-2019
Mie University
2014-2016
Abstract The subarctic North Pacific is a high-nutrient low-chlorophyll region in which decoupling of dissolved iron (dFe) and macronutrient an essential control primary production. In this study, we evaluated the influence decadal-scale climate changes on net production (NPP) by performing hindcast experiment for 1979–2016 using ice–ocean coupled model with simple biogeochemical cycle. Simulation results show significant NPP decrease subtropical–subarctic gyre boundary (SGB) since 1990s;...
Subtropical Mode Water (STMW), characterized by vertically uniform temperature of ~17°C, is distributed horizontally over 5000 kilometers at the 100- to 500-meter depths in subtropical North Pacific Ocean. Its formation and spreading fluctuate relation Decadal Oscillation Kuroshio path variation, but feedback from STMW on sea surface (SST) overlying atmosphere remains unclear. Using Argo profiling float data, we show that south Japan, whose thickness varies decadally, modulates thermal...
Abstract Since August 2017, the Kuroshio has taken a large-meander (LM) path, which forced extension (KE) to be in its stable state against wind-forced decadal variability. How such current conditions have impacted formation and advection of North Pacific subtropical mode water (STMW) over distribution region was examined using Argo float data during 2005–2020. Out whole STMW defined as low-potential vorticity layer 16–19.5 ºC, relatively cold variety 16–18 formed south KE advected westward...
Abstract Sea surface temperature (SST) fronts in mid- to high-latitude oceans have significant impacts on extratropical atmospheric circulations and climate. In the western subarctic Pacific, sharp SST form between cold water recently found quasi-stationary jets that advect warm waters originating Kuroshio northeastward. Here we present a new mechanism of jet formation paying attention propagation baroclinic Rossby waves is deflected by eddy-driven barotropic flows over bottom rises,...
Abstract Since August 2017, the large meander (LM) path of Kuroshio south Japan has continued to date for more than five years, with a local recirculation gyre off Shikoku (RGOS). The formation and temporal evolution Subtropical Mode Water (STMW) in isolated RGOS were examined by using Argo profiling float shipboard observation data. late winter 2018, which was first current LM event, multiple STMW layers different densities overlapping each other have been observed three years inside RGOS....
Abstract Two mesoscale convective events in the baiu frontal zone (BFZ) were documented, based on intensive atmospheric soundings and oceanic castings East China Sea during May 2011, addition to continuous surface meteorological observations, satellite products, objective analyses. These occurred while BFZ was nearly stagnant a mesolow deepening zone. Near-surface southerlies associated with low-level jet transported warm, humid air mass from south of BFZ. Enhanced evaporation, which mainly...
Abstract. Between 1950 and 2012, boreal summer (rainy season) rainfall in the Sahel changed from a multi-decadal decreasing trend to an increasing (positive shift) mid-1980s. We found that this shift was synchronous with similar shifts global oceanic evaporation land precipitation on all continents except Americas. The occurred mainly Southern Hemisphere (SH) subtropical oceans of Northern (NH). Because increased strengthens atmospheric moisture transport toward areas, synchrony is...
Abstract Some of the heaviest snowfalls in urban areas world occur Japan, particularly regions that face Japan Sea. Many heavy are produced by a Sea polar air mass convergence zone (JPCZ), which is an atmospheric river-like cloud forms when Siberian cold flows over warm Quantifying how air–sea interaction strengthens JPCZ key to snowfall prediction. However, until our observations with hourly meteorological balloon launches from training vessel 2022, no simultaneous targeting had been...
The interbasin exchange between the Sea of Okhotsk and North Pacific governs intermediate water ventilation fertilization nutrient-rich subpolar Pacific, thus has an enormous influence on Pacific. However, mechanism this is puzzling; current studies have not explained how western boundary (WBC) subarctic intrudes only partially into Okhotsk. High-resolution models often exhibit unrealistically small exchanges, as WBC overshoots passing by deep straits does induce flows. Therefore, partial...
Previous modeling studies have indicated that the Oyashio front in subarctic Pacific Ocean significantly affects atmosphere on meso- to basin scales; however, there were no situ observations captured oceanic imprints this region as far authors know. We present evidence of atmospheric responses by using a total 103 radiosondes launched around April 2013 with continuous surface meteorology and ceilometer observations. Composite profiles showed low-level below 1000 m was statically stable cold...
Abstract To confirm whether surface winds strengthen above warm waters around oceanic fronts using in situ data, a field measurement was conducted both expendable bathythermographs and Global Positioning System sondes released concurrently across the Kuroshio front East China Sea December 2010. In contrast to previous studies mainly based on satellite observations, finding of present survey is local weakening at northern flank front. From observation conjunction with regional numerical model...
Abstract Radiosondes were launched in August 2006 from a research vessel above spot around the Kuril Islands between North Pacific and Okhotsk Sea characterized by an extremely cold sea surface temperature (SST) large horizontal gradient caused strong tidal mixing. Because this SST was solely oceanic process, observed data chiefly reflect influence on atmosphere. In area, where summertime is typically lower than other seas same latitude belt, minimum of 2°C 7°C/10 km 2006. During cruise,...
Abstract Simultaneous launches of radiosondes were conducted from three research vessels aligned meridionally across a sea surface temperature (SST) front on the flank Kuroshio Extension. The soundings carried out every 2 h over 5 days in early July 2012 provided unique opportunity capturing unambiguous data anomalous easterly winds derived pronounced meridional SST gradient. indicate that contrast heat fluxes underlying ocean enhanced air anomaly front, which was observed up to 300-m...
Abstract. Between 1950 and 2012, summer (rainy season) rainfall in the Sahel changed from a multi-decadal decreasing trend to an increasing (positive shift) mid-1980s. We found that this shift was synchronous with similar shifts global oceanic evaporation land precipitation all continents except Americas. The occurred mainly Southern Hemisphere (SH) subtropical oceans of Northern (NH). Because increased strengthens atmospheric moisture transport toward areas, synchrony is reasonable. Surface...