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Polar deserts (also seen as "cold deserts") have similar features, except the main form of precipitation is snow rather than rain. Antarctica is the world's largest cold desert (composed of about 98% thick continental ice sheet and 2% barren rock).
Desertification is a gradual process of increased soil aridity.Desertification has been defined in the text of the United Nations Convention to Combat Desertification (UNCCD) as "land degradation in arid, semi-arid and dry sub-humid regions resulting from various factors, including climatic variations and human activities."
Desert ecology is the study of interactions between both biotic and abiotic components of desert environments. A desert ecosystem is defined by interactions between organisms, the climate in which they live, and any other non-living influences on the habitat. Deserts are arid regions that are generally associated with warm temperatures; however ...
Desert pavement evolution. Desert pavement surfaces are often coated with desert varnish, a dark brown, sometimes shiny coating that contains clay minerals. In the US a famous example can be found on Newspaper Rock in southeastern Utah. Desert varnish is a thin coating (patina) of clays, iron, and manganese on the surface of sun-baked boulders.
Tropical deserts are located in regions between 15 and 30 ... Natural gas and oil are complex hydrocarbons that formed millions of years ago from the decomposition of ...
The lower part of the piedmont is a bajada, with the distinction being that the upper pediment surface is cut into bedrock (with possibly a thin veneer of alluvium) and is thus a result of erosion, while the lower bajada is aggradational (formed by accumulation of fresh sediments). Above the pediment, the slope abruptly increases, with an angle ...
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Ripples [1] and dunes [2] form as a natural self-organizing response to sediment transport. Aeolian sediment transport is common on beaches and in the arid regions of the world, because it is in these environments that vegetation does not prevent the presence and motion of fields of sand.