A desert is a barren area of landscape where little precipitation occurs and, consequently, living conditions are hostile for plant and animal life. The lack of vegetation exposes the unprotected surface of the ground to denudation. About one-third of the land surface of the Earth is arid or semi-arid. This includes much of the polar regions, where little precipitation occurs, and which are sometimes called polar deserts or "cold deserts". Deserts can be classified by the amount of precipitation that falls, by the temperature that prevails, by the causes of desertification or by their geographical location.
Deserts are formed by weathering processes as large variations in temperature between day and night put strains on the rocks, which consequently break in pieces. Although rain seldom occurs in deserts, there are occasional downpours that can result in flash floods. Rain falling on hot rocks can cause them to shatter, and the resulting fragments and rubble strewn over the desert floor are further eroded by the wind. This picks up particles of sand and dust, which can remain airborne for extended periods – sometimes causing the formation of sand storms or dust storms. Wind-blown sand grains striking any solid object in their path can abrade the surface. Rocks are smoothed down, and the wind sorts sand into uniform deposits. The grains end up as level sheets of sand or are piled high in billowing sand dunes. Other deserts are flat, stony plains where all the fine material has been blown away and the surface consists of a mosaic of smooth stones, often forming desert pavements, and little further erosion takes place. Other desert features include rock outcrops, exposed bedrock and clays once deposited by flowing water. Temporary lakes may form and salt pans may be left when waters evaporate. There may be underground sources of water, in the form of springs and seepages from aquifers. Where these are found, oases can occur.
Plants and animals living in the desert need special adaptations to survive in the harsh environment.
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The course is part of a three-year trajectory dedicated to a comprehensive history of domestic space and its relationship with urban form from its prehistoric origins to Neoliberal times.
A quoi peut servir un.e architecte ?
Nous réfléchirons ensemble à cette question à travers un projet de réinvention et réhabilitation de l'Institut Thérapeutique Educatif et Pédagogique (ITEP) les Éve
A quoi peut servir un.e architecte ?
Nous réfléchirons ensemble à cette question à travers un projet de réinvention et réhabilitation de l'Institut Thérapeutique Educatif et Pédagogique (ITEP) les Éve
Aridification is the process of a region becoming increasingly arid, or dry. It refers to long term change, rather than seasonal variation. It is often measured as the reduction of average soil moisture content. It can be caused by reduced precipitation, increased evaporation, lowering of water tables, and changes in ground cover acting individually or in combination. Its major consequences include reduced agricultural production, soil degradation, ecosystem changes and decreased water catchment runoff.
The desert climate or arid climate (in the Köppen climate classification BWh and BWk) is a dry climate sub-type in which there is a severe excess of evaporation over precipitation. The typically bald, rocky, or sandy surfaces in desert climates are dry and hold little moisture, quickly evaporating the already little rainfall they receive. Covering 14.2% of Earth's land area, hot deserts are the second most common type of climate on Earth after the polar climate.
Polar deserts are the regions of Earth that fall under an ice cap climate (EF under the Köppen classification). Despite rainfall totals low enough to normally classify as a desert, polar deserts are distinguished from true deserts ( () or () under the Köppen classification) by low annual temperatures and evapotranspiration. Most polar deserts are covered in ice sheets, ice fields, or ice caps, and they are also called white deserts. Polar deserts are one of two polar biomes, the other being Arctic tundra.
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