Orography is the average height of land, measured in geopotential meters, over a certain domain. In geoscientific models, such as general circulation models, orography defines the lower boundary (except where there is ocean, of course). Because orography is spatially averaged, for example the height of the Himalaya mountains will depend on horizontal resolution. The higher the horizontal resolution, the better the orography will follow the actual terrain. A general circulation model (GCM) aims to describe geophysical flow by integrating a variety of fluid-dynamical, chemical, or even biological equations that are either derived directly from physical laws (e. ... The Himalaya is a mountain range in Asia, separating the Indian subcontinent from the Tibetan Plateau. ... The image resolution is a term that says something about how much image detail an image can hold. ...

When a river's tributaries or settlements by the river are listed in orographic sequence, they are in order from the highest (nearest the source of the river) to the lowest (nearest the mouth). A tributary (or affluent or confluent) is a contributory stream, a river that does not reach the sea, but joins another major river (a parent river), to which it contributes its waters, swelling its discharge. ...

Orographic precipitation

Orographic precipitation, also known as relief precipitation, is precipitation generated by a forced upward movement of air upon encountering a physiographic upland (see anabatic wind). This upwards movement cools the air, resulting in a cloud formation and rainfall. In parts of the world subjected to relatively consistent winds (for example the trade winds), a wetter climate prevails on the windward side of a mountain than on the leeward (downwind) side as moisture is removed by orographic precipitation. Drier air (see katabatic wind) is left on the descending, generally warming, leeward side where a rain shadow is formed. An anabatic wind is a wind which blows up a steep slope or mountain side. ... Cumulus of fair weather A cloud is a visible mass of condensed water droplets or ice crystals suspended in the atmosphere above Earths (or another planetary bodys) surface. ... Wind is the quasi-horizontal movement of air (as opposed to an air current) caused by a horizontal pressure gradient force. ... The trade winds are a pattern of wind found in bands around Earths equatorial region. ... A katabatic wind, from the Greek word katabatikos meaning going downhill, is a wind that blows down a topographic incline such as a hill, mountain, or glacier. ... A rain shadow (or more accurately, precipitation shadow) is a dry region on the surface of the Earth that is leeward or behind a mountain with respect to the prevailing wind direction. ...

Orographic precipitation is well known on oceanic islands, such as the Hawaiian Islands, where much of the rainfall received on an island is on the windward side, and the leeward side tends to be quite dry, almost desert-like, by comparison. This phenomenon results in substantial local gradients of average rainfall, with coastal areas receiving on the order of 20 to 30 inches (500 to 750 mm) per year, and interior uplands receiving over 100 inches (2,500 mm) per year. Leeward coastal areas are especially dry—less than 20 in (500 mm) per year at Waikiki—and the tops of moderately high uplands are especially wet—about 475 in (12,000 mm) per year at Wai'ale'ale on Kaua'i. The Hawaiian Islands are an archipelago of numerous islands and atolls trending northwest by southeast in the North Pacific Ocean between latitudes 19° N and 29° N. The archipelago takes as its name that of the largest island in the group. ... A dune in the Egyptian desert Desert in California In geography, a desert is a landscape form or region that receives little precipitation. ... Waikīkī is a neighborhood of Honolulu, in the City and County of Honolulu, on the south shore of the Island of O‘ahu, Hawai‘i. ... Kauai from space (NASA image) Kaua‘i (usually called Kauai outside the Hawaiian Islands) is the oldest and fourth largest of the main Hawaiian Islands. ...

See Also

Orographic lift Orographic lift occurs when moisture-carrying clouds floating over lower-elevation terrain move over rising terrain. ...