High-pressure area Hadley cells help form the subtropical ridge, steer tropical waves and tropical cyclones across the ocean and is strongest during the summer. The subtropical ridge also helps form most of the world's deserts. On English-language weather maps, high-pressure centers are identified by the letter H. Weather maps in other languages may use different letters or symbols. The direction of wind flow around an atmospheric high-pressure area and a low-pressure area, as seen from above, depends on the hemisphere. High-pressure systems rotate clockwise in the northern Hemisphere; low-pressure systems rotate clockwise in the southern hemisphere. The scientific terms in English used
Low pressure receptors Low pressure receptors Low pressure receptors are baroreceptors located in large systemic veins, in the pulmonary arteries, in the walls of the atria, and ventricles of the heart.[2] They are also called volume receptors. These receptors respond to changes in the wall tension, which is proportional to the filling state of the low pressure side of circulation (below 60mmHg). Thus, low pressure baroreceptors are involved with the regulation of blood volume. The blood volume determines the mean pressure throughout the system, in particular in the venous side where most of the blood is held. Increasing stretch of the receptors stimulates