FUTURE CHANGES IN L2 STORM SURGE IN ISE BAY DOWNSCALED DIRECTLY FROM LARGE ENSEMBLE CLIMATE SIMULATIONS d4PDF

Abstract A large-ensemble climate simulation database, which is known as the database for policy decision-making for future climate changes (d4PDF), was designed for climate change risk assessments. Since the completion of the first set of climate simulations in 2015, the database has been growing continuously. It contains the results of ensemble simulations conducted over a total of thousands years respectively for past and future climates using high-resolution global (60 km horizontal mesh) and regional (20 km mesh) atmospheric models. Several sets of future climate simulations are available, in which global mean surface air temperatures are forced to be higher by 4 K, 2 K, and 1.5 K relative to preindustrial levels. Nonwarming past climate simulations are incorporated in d4PDF along with the past climate simulations. The total data volume is approximately 2 petabytes. The atmospheric models satisfactorily simulate the past climate in terms of climatology, natural variations, and extreme events such as heavy precipitation and tropical cyclones. In addition, data users can obtain statistically significant changes in mean states or weather and climate extremes of interest between the past and future climates via a simple arithmetic computation without any statistical assumptions. The database is helpful in understanding future changes in climate states and in attributing past climate events to global warming. Impact assessment studies for climate changes have concurrently been performed in various research areas such as natural hazard, hydrology, civil engineering, agriculture, health, and insurance. The database has now become essential for promoting climate and risk assessment studies and for devising climate adaptation policies. Moreover, it has helped in establishing an interdisciplinary research community on global warming across Japan.

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ESTIMATION OF WORST-CLASS TROPICAL CYCLONE AND STORM SURGE, AND ITS RETURN PERIOD -CASE STUDY FOR ISE BAY-

Journal of Japan Society of Civil Engineers Ser B2 (Coastal Engineering) ◽

10.2208/kaigan.71.i_1513 ◽

2015 ◽

Vol 71 (2) ◽

pp. I_1513-I_1518 ◽

Cited By ~ 1

Author(s):

Yoko SHIBUTANI ◽

Sota NAKAJO ◽

Nobuhito MORI ◽

Sooyoul KIM ◽

Hajime MASE

Keyword(s):

Tropical Cyclone ◽

Storm Surge ◽

Return Period ◽

Ise Bay

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Interhemispheric asymmetry of climate change projections of boreal winter surface winds in CanESM5 large ensemble simulations

10.21203/rs.3.rs-476108/v1 ◽

2021 ◽

Author(s):

Bin Yu ◽

Xuebin Zhang ◽

Guilong Li ◽

Wei Yu

Keyword(s):

Climate Variability ◽

Wind Power ◽

Atmospheric Circulation ◽

Large Scale ◽

Boreal Winter ◽

Interhemispheric Asymmetry ◽

Large Ensemble ◽

Internal Climate Variability ◽

Climate Simulations ◽

Extreme Wind

Abstract A recent study of future changes in global wind power using an ensemble of ten CMIP5 climate simulations indicated an interhemispheric asymmetry of wind power changes over the 21st century, featured by power decreases across the Northern Hemisphere mid-latitudes and increases across the tropics and subtropics of the Southern Hemisphere. Here we analyze future global projections of surface mean and extreme winds by means of a single-model initial-condition 50-member ensemble of climate simulations generated with CanESM5, the Canadian model participated in CMIP6. We analyze the ensemble mean and spread of boreal winter mean and extreme wind trends over the next half-century (2021-2070) and explore the contribution of internal climate variability to these trends. Surface wind speed is projected to mostly decrease in northern mid-low latitudes and southern mid-latitudes and increase in northern high latitudes and southern tropical and subtropical regions, with considerable regional variations. Large ensemble spreads are apparent, especially with remarkable differences over northern parts of South America and northern Russia. The interhemispheric asymmetry of wind projections is found in most ensemble members, and can be related to large-scale changes in surface temperature and atmospheric circulation. The extreme wind has similar structure of future projections, whereas its reductions tend to be more consistent over northern mid-latitudes. The projected mean and extreme wind changes are attributed to changes in both externally anthropogenic forced and internal climate variability generated components. The spread in wind projections is partially due to large-scale atmospheric circulation variability.

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Storm Surge Inundation Analysis with Consideration of Building Shape and Layout at Ise Bay by Maximum Potential Typhoon

Journal of Marine Science and Engineering ◽

10.3390/jmse8121024 ◽

2020 ◽

Vol 8 (12) ◽

pp. 1024

Author(s):

Masaki Nimura ◽

Shuzo Nishida ◽

Koji Kawasaki ◽

Tomokazu Murakami ◽

Shinya Shimokawa

Keyword(s):

Global Warming ◽

High Resolution ◽

Sea Level ◽

Storm Surge ◽

High Velocity ◽

High Tide ◽

Disaster Mitigation ◽

Ise Bay ◽

Building Shape ◽

Tide Level

Global warming is feared to cause sea-level rise and intensification of typhoons, and these changes will lead to an increase in storm surge levels. For that reason, it is essential to predict the inundation areas for the maximum potential typhoon and evaluate the disaster mitigation effect of seawalls. In this study, we analyzed storm surge inundation of the inner part of Ise Bay (coast of Aichi and Mie Prefecture, Japan) due to the maximum potential typhoon in the future climate with global warming. In the analysis, a high-resolution topographical model was constructed considering buildings’ shape and arrangement and investigated the inundation process inside the seawall in detail. The results showed that buildings strongly influence the storm surge inundation process inside the seawall, and a high-velocity current is generated in some areas. It is also found that closing the seawall door delays the inundation inside the seawall, but the evacuation after inundation is more difficult under the seawall doors closed condition than opened condition when the high tide level exceeds the seawall.

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Over 5,000 Years of Ensemble Future Climate Simulations by 60-km Global and 20-km Regional Atmospheric Models

Bulletin of the American Meteorological Society ◽

10.1175/bams-d-16-0099.1 ◽

2017 ◽

Vol 98 (7) ◽

pp. 1383-1398 ◽

Cited By ~ 119

Author(s):

Ryo Mizuta ◽

Akihiko Murata ◽

Masayoshi Ishii ◽

Hideo Shiogama ◽

Kenshi Hibino ◽

...

Keyword(s):

Twentieth Century ◽

Extreme Events ◽

General Circulation ◽

Dynamical Downscaling ◽

Circulation Model ◽

Future Climate ◽

Future Climate Change ◽

Atmospheric Models ◽

Large Ensemble ◽

Climate Simulations

Abstract An unprecedentedly large ensemble of climate simulations with a 60-km atmospheric general circulation model and dynamical downscaling with a 20-km regional climate model has been performed to obtain probabilistic future projections of low-frequency local-scale events. The climate of the latter half of the twentieth century, the climate 4 K warmer than the preindustrial climate, and the climate of the latter half of the twentieth century without historical trends associated with the anthropogenic effect are each simulated for more than 5,000 years. From large ensemble simulations, probabilistic future changes in extreme events are available directly without using any statistical models. The atmospheric models are highly skillful in representing localized extreme events, such as heavy precipitation and tropical cyclones. Moreover, mean climate changes in the models are consistent with those in phase 5 of the Coupled Model Intercomparison Project (CMIP5) ensembles. Therefore, the results enable the assessment of probabilistic change in localized severe events that have large uncertainty from internal variability. The simulation outputs are open to the public as a database called “Database for Policy Decision Making for Future Climate Change” (d4PDF), which is intended to be utilized for impact assessment studies and adaptation planning for global warming.

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