Arakawa River (Kantō) Arakawa River (Kantō) The is a long river that flows through Saitama Prefecture and Tokyo. It originates on Mount Kobushi in Saitama Prefecture, and empties into Tokyo Bay. It has a total catchment area of . The river is one of Tokyo's major sources of tap water, and together with the Tone River, accounts for around 80% of Tokyo's water supply. Attempts to control flooding of the Arakawa River have been made since the area that is now Tokyo became the de facto capital of Japan during the Edo period. Following a major flood in 1910 that damaged a large
Arakawa grids Arakawa grids The Arakawa grid system depicts different ways to represent and compute orthogonal physical quantities (especially velocity- and mass-related quantities) on rectangular grids used for Earth system models for meteorology and oceanography. For example, the Weather Research and Forecasting Model uses the Arakawa Staggered C-Grid in its atmospheric calculations when using the ARW core. The five Arakawa grids (A-E) were first introduced in Arakawa and Lamb 1977. For an image of the five grids, see the following picture, or Fig. 1 in Purser and Leslie 1988. The "unstaggered" Arakawa A-grid evaluates all quantities at the same point on each