Arakawa, Tokyo Arakawa, Tokyo Arakawa has sister-city relationships with Donaustadt in Vienna, Austria, and with Corvallis, Oregon, U.S. Domestically, it has similar relationships with nine cities, towns and villages. As of May 1, 2015, the ward has an estimated population of 208,763, and a population density of about 20,550 persons per km². The total area is 10.16 km². Arakawa is in the northeastern part of Tokyo. The shape is long and narrow, stretching from west to east. The Sumida River forms the northern boundary. The ward is surrounded by five other special wards. To the north lies Adachi; to the west, Kita;
Arakawa grids a single face of the rectangular domain. Haltiner, G. J., and R. T. Williams, 1980. Numerical Prediction and Dynamic Meteorology. John Wiley and Sons, New York. 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