(Invited Talk) Toward forecasting and understanding the mechanisms of extremes in urban areas

Weather and climate in coastal-urban areas are influenced by complex

interactions among the ocean, atmosphere and the thermal environment in

urban areas. Extreme weather in urban areas such as local heavy rain in

summer season seems to be influenced by heat content in urban areas.

However, it is still unclear whether urban heat content is one of the

main reasons for extremes in cities.

The Multi-Scale Simulator for the Geoenvironment (MSSG), which is a

coupled non-hydrostatic atmosphere-ocean model, has been developed at

the Earth Simulator Center. MSSG can resolve the building scale and

compute three dimensional flow along an urban building canyon. MSSG-A,

which is an atmospheric component of MSSG, is characterized as a

non-hydrostatic model and introduces LES for the turbulence model.

In this presentation, as a first step to understanding the mechanisms of

local extremes in urban areas, especially the Tokyo region, preliminary

results from high resolution simulations on the Earth Simulator will be

demonstrated and near future research plans will be introduced.