Abstract: In this paper the west wind circulation along the meridians 135°E, 135°W, 65°W and 15°W during the period July 1945 through January 1946 are discussed. The circulations along these four longitudes are remarkably different, being simple and intense along the east coasts (135°E, 65°W) and weak and complex along the west coasts (135°W, 15°W). Over the entire northern hemisphere the westerlies tend to split over three regions, namely, the two west coasts and Tibetan plateau. Downstream from these places the split westerlies join into. one strong jet stream, the intensity of the jet stream off the Asiatic coast being the highest. This phenomenon is attributed to the orographical influence of the mountains on the general circulation. Since the west wind speed is higher along the east coast than the,west coasts, there is due to advection an accumulation of kinetic energy over the ocean and deplation of kinetic energy over the continents. To maintain a steady state kinetic energy must be constantly produced over the land and constantly consumed over the water. In winter the continent is colder than the ocean. Owing to this thermal contrast the trough point along one isobar tends to slope northward from the coast toward water and slope southward from the coast toward land.