Low-pressure area This generates a steady wind blowing toward the land, bringing the moist near-surface air over the oceans with it. Similar rainfall is caused by the moist ocean-air being lifted upwards by mountains, surface heating, convergence at the surface, divergence aloft, or from storm-produced outflows at the surface. However the lifting occurs, the air cools due to expansion in lower pressure, which in turn produces condensation. In winter, the land cools off quickly, but the ocean keeps the heat longer due to its higher specific heat. The hot air over the ocean rises, creating a low-pressure area and a breeze from
Pressure carburetor fairly simple to operate compared to float carbureted engines. The four chambers in the pressure carburetor are all in a row and are referred to by letters. Chamber A contains impact air pressure at the carburetor inlet. Chamber B contains the lower air pressure from the throat of the venturi. The difference in pressure between the two air chambers creates what is known as the "air metering force", which acts to open the servo valve. Chamber C contains metered fuel, and chamber D contains unmetered fuel. The difference in pressure between the two fuel chambers creates the "fuel metering force",