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
Pressure-sensitive paint error sources by employing a second probe into the paint layer, known as the reference probe. This reference probe is used to ratio out the effects of these errors producing high quality PSP pressure maps at low speeds. Pressure-sensitive paint Pressure-sensitive paint (PSP) is a method for measuring air pressure or local oxygen concentration, usually in aerodynamic settings. PSP is paint-like coating which fluoresces under a specific illumination wavelength in differing intensities depending on the external air pressure being applied locally to its surface. A model surface is painted with the PSP coating with an airbrush or automotive type paint