A5007702365- Oceanographic and Atmospheric Processes
- Climate variability and models
- Arctic and Antarctic ice dynamics
- Meteorological Phenomena and Simulations
- Marine and coastal ecosystems
- Methane Hydrates and Related Phenomena
- Geophysics and Gravity Measurements
- Cryospheric studies and observations
- Geology and Paleoclimatology Research
- Climate change and permafrost
- Atmospheric and Environmental Gas Dynamics
- Marine and fisheries research
- Tropical and Extratropical Cyclones Research
- Image Retrieval and Classification Techniques
- Ocean Waves and Remote Sensing
- Coastal and Marine Dynamics
- Advanced Image and Video Retrieval Techniques
- Atmospheric Ozone and Climate
- Reservoir Engineering and Simulation Methods
- Marine and environmental studies
- Cephalopods and Marine Biology
- Medical Image Segmentation Techniques
- Isotope Analysis in Ecology
- Hydrocarbon exploration and reservoir analysis
- Atmospheric chemistry and aerosols
Japan Meteorological Agency
2016-2025
Meteorological Research Institute
2016-2025
Nagoya University
2023
Kyoto University
2003-2019
Kyoto University Institute for Chemical Research
2019
The University of Tokyo
2018
Foundation for International Environmental Law and Development
2014
Japan Agency for Marine-Earth Science and Technology
2006-2010
Tokyo Institute of Technology
2005-2008
Institute for Global Environmental Strategies
2007
Abstract We examine CMIP6 simulations of Arctic sea‐ice area and volume. find that models produce a wide spread mean area, capturing the observational estimate within multimodel ensemble spread. The provides more realistic sensitivity September to given amount anthropogenic CO 2 emissions global warming, compared with earlier CMIP experiments. Still, most fail simulate at same time plausible evolution surface temperature. In vast majority available simulations, Ocean becomes practically free...
Uncertainty in ocean analysis methods and deficiencies the observing system are major obstacles for reliable reconstruction of past climate. The variety existing reanalyses is exploited a multi-reanalysis ensemble to improve state estimation gauge uncertainty levels. ensemble-based signal-to-noise ratio allows identification characteristics which robust (such as tropical mixed-layer-depth, upper heat content), where large exists (deep ocean, Southern Ocean, sea ice thickness, salinity),...
Global and regional ocean sea ice reanalysis products (ORAs) are increasingly used in polar research, but their quality remains to be systematically assessed. To address this, the Polar ORA Intercomparison Project (Polar ORA-IP) has been established following on from ORA-IP project. Several aspects of ten selected ORAs Arctic Antarctic were addressed by concentrating comparing mean states terms snow, ice, transports hydrography. Most diagnostics carried out for first time such an extensive...
Decadal-scale climate variations over the Pacific Ocean and its surroundings are strongly related to so-called decadal oscillation (PDO) which is coherent with wintertime North America Asian monsoon, have important impacts on marine ecosystems fisheries. In a near-term prediction covering period up 2030, we require knowledge of future state internal in system such as PDO well global warming signal. We perform sets ensemble hindcast forecast experiments using coupled atmosphere-ocean model...
A new high-resolution atmosphere-ocean coupled general circulation model named MIROC4h has been developed, and its performance in a 120-year control experiment (including 50-year spin-up) under the present conditions (the year 1950) is examined. The results of by are compared with simulations preindustrial carried out for Intergovernmental Panel on Climate Change Fourth Assessment Report (IPCC AR4) using previous high- medium-resolution versions model, called MIROC3h MIROC3m, respectively....
Recent observational surveys have shown significant oceanic bottom-water warming. However, the mechanisms causing such warming remain poorly understood, and their time scales are uncertain. Here, we report computer simulations that reveal a fast teleconnection between changes in surface air-sea heat flux off Adélie Coast of Antarctica North Pacific. In contrast to conventional estimates multicentennial scale, this link is established over only four decades through action internal waves....
[1] We calculated basin-scale and global ocean decadal temperature change rates from the 1990s to 2000s for waters below 3000 m. Large increases were detected around Antarctica, a relatively large increase was along northward path of Circumpolar Deep Water in Pacific. The heat content (HC) estimated m 0.8 × 1022 J decade−1; value that cannot be neglected precise estimation balance. We reproduced observed changes deep using data assimilation system examined virtual observations field evaluate...
Accurate knowledge of the location and magnitude ocean heat content (OHC) variability change is essential for understanding processes that govern decadal variations in surface temperature, quantifying changes planetary energy budget, developing constraints on transient climate response to external forcings. We present an overview temporal spatial characteristics OHC as represented by ensemble dynamical statistical reanalyses (ORAs). Spatial maps 0–300 m layer show large regions Pacific...
We produced a four-dimensional variational ocean re-analysis for the Western North Pacific over 30 years (FORA-WNP30). It is first-ever dataset covering western 3 decades at eddy-resolving resolution. The analysis scheme version of Meteorological Research Institute Multivariate Ocean Variational Estimation system (MOVE-4DVAR) employed to conduct long-term reanalysis experiment during 1982–2012. After evaluating basic performance FORA-WNP30, interannual decadal variability analyzed. Overall,...
Sixteen monthly air–sea heat flux products from global ocean/coupled reanalyses are compared over 1993–2009 as part of the Ocean Reanalysis Intercomparison Project (ORA-IP). Objectives include assessing closure, consistency temporal variability, comparison with other products, and documenting errors against in situ measurements at a number OceanSITES moorings. The ensemble 16 ORA-IP estimates has positive bias 4.2 ± 1.1 W m−2. Residual gain (i.e., surface + assimilation increments) is...
Abstract. We compare the mass budget of Arctic sea ice for 15 models submitted to latest Coupled Model Intercomparison Project (CMIP6), using new diagnostics that have not been available previous model inter-comparisons. These allow us look beyond standard metrics cover and thickness processes growth loss in climate a more detailed way than has previously possible. For 1960–1989 multi-model mean, dominant causing annual are basal frazil formation, which both occur during winter. The main by...
Abstract The observational network around the North Atlantic has improved significantly over last few decades with subsurface profiling floats and satellite observations recent efforts to monitor Meridional Overturning Circulation (AMOC). These have shown decadal time scale changes across including in heat content, transport, circulation. However, there are still significant gaps coverage. Ocean reanalyses integrate a dynamically consistent ocean model can be used understand observed...
A four‐dimensional variational (4D‐VAR) data assimilation system using a coupled ocean‐atmosphere global model has been successfully developed with the aim of better defining dynamical states climate on seasonal to interannual scales. The application this state estimations processes during 1996–1998 period shows, in particular, that representations structures associated several key events tropical Pacific and Indian Ocean sector (such as El Niño, dipole, Asian summer monsoon) are...
This paper presents a proposal of general framework that explicitly models local information and global in conditional random field. The proposed method extracts image features as well ones uses them to predict the scene input image. Scene-based top-down is generated based on predicted scene. It represents spatial configuration labels category compatibility over an Incorporation helps resolve ambiguities achieves locally globally consistent recognition. In spite model's simplicity,...
The impact of using sea surface salinity (SSS) data derived from the Aquarius satellite within a global ocean assimilation system is investigated. In central‐eastern North Pacific, more realistic SSS structures introduced by also influence salinity, temperature and potential vorticity fields obtained in subsurface layer via enhanced mode‐water formation. Around Indonesian maritime continent, leads to distributions which are closer buoy observations, while region Amazon River plume,...
Abstract The effect of Langmuir circulation (LC) on vertical mixing is parameterized in the ocean mixed layer model (OMLM), based analysis large-eddy simulation (LES) results. Parameterization LC effects carried out terms modifications length scale as well inclusion contribution from Stokes force momentum and TKE equations. performance new OMLM examined by comparing with LES results, together sensitivity tests for empirical constants used parameterization. then applied to general (OGCM)...
The Kuroshio Extension (KE) flows eastward at the northern boundary of North Pacific subtropical gyre. By transporting large amounts seawater with heat, KE contributes significantly to formation sea surface temperature (SST) fields. Recently, poleward shifts major ocean gyres in world ocean, including gyre, have been highlighted based on basin-scale changes SST and height (SSH) distributions. However, a detailed investigation long-term meridional movement has not presented. Investigation...