Saitama (city) city boundaries. The western portion of the city lies on the lowland created by the Arakawa River along with those created by small rivers such as the Moto-Arakawa River, Shiba River, and Ayase River. The rest of the area mostly resides on the Ōmiya Plateau lying in the north-south direction. Dispersed in this region, major rivers flow southward, almost paralleling to one another. Saitama has ten wards ("ku"), which were assigned official colours as of April 2005: Saitama's economy is principally constituted by commercial business. The city is one of many commercial centers of the Greater Tokyo area and serves
Arakawa grids grid cell, e.g., at the grid center or at the grid corners. The Arakawa A-grid is the only unstaggered grid type. The "staggered" Arakawa B-grid separates the evaluation of the two sets of quantities. e.g., one might evaluate velocities at the grid center and masses at grid corners. The "staggered" Arakawa C-grid further separates evaluation of vector quantities compared to the Arakawa B-grid. e.g., instead of evaluating both east-west (u) and north-south (v) velocity components at the grid center, one might evaluate the u components at the centers of the left and right grid faces, and the v components at