An atmosphere, ocean waves, and ocean current coupled model system is extended to include the atmosphere land surface interactions and to connect the water heat and material circulation between the ocean and terrestrial circulation systems. The models used in this system are the non-hydrostatic atmospheric model (MM5), multi-layer land surface model (SOLVEG2), hydrological simulation program FORTRAN (HSPF), the third-generation ocean wave model of NOAA (WAVE WATCH III), and the Princeton Ocean Model (POM). The modeling system is divided into two main wings; the atmosphere-ocean wing, and the atmosphere-land surface wing. Both wings are combined to give a coupled atmosphere, land surface, hydrology, ocean wave, and ocean current model (ALHOM) that is capable to simulate the hydrological cycle on a regional scale. The coupled modeling system is a main part of currently running research project Asia Environmental Simulator (AES). Within AES the coupled modeling system will be applied for simulating water circulation and CO2 budgets in Kapuas river basin in Kalimantan Island, Indonesia, and for water circulation and water quality in Haji dam watershed in Hiroshima prefecture, Japan.