ds =* westerlies =* polar frontlatitude belts of circulation:* equatorial low- region of ascending, warm, moist air* trade winds- 0-20 degrees latitude * subtropical high pressure- 20-30 degrees latitude* westerlies- 30-50 degrees latitude (mid)* easterlies- 50 degree latitude (high)* polar high- region of descending cold, dry airfactors controlling climate: (average weather and its variability)* variables: temperature, rain, clouds, wind* global air circulation (latitude belts of circulation)* distribution of land and sea (oceans, currents, continents)* topography of the land (mountains, plateausGeologic Processes of Windtransport of sediment:* wind-blown sand (low altitude)* surface creep- rolling motion of sand* saltation- moving sand grains by hopping (3/4 moves this way)* sand ripples- linear ridges of sand perpendicular to wind direction (sorting)* wind-blown dust (faster and larger)* mobilization of dust-dust in the laminar air flow is NOT mobilized-dust is mobilized by turbulence* transport of dust (wind's suspended load)-gravity pulls dust down-wind turbulence carries dust forward* dust storms- large scale dust transport (drought) (low visibility)-thin-windward, thick-leeerosion:* deflation- pick-up and removal of loose material* deflation hollows and basins (little vegetation) (Quattara Depression) (1m/yr)* desert pavement- continuous cover of oversized alluvium "cobble"* abrasion- shaping and polishing of rock surfaces* ventrifacts- any abraded bedrock surface (1 smooth upwind surface)* yardangs- streamlined, wind-eroded ridge (groups)-differential deflationeolian deposits-sand:* dunes- hill or ridge of sand formed by deposition of sand on the leeward side (slip face) (avalanche)* form- asymmetrical in cross-section; with a gentle windward slope and steep slip face* size- determined by maximum wind velocity; typically 30-100m, rarely 500m* types--barchan dune- limited sand, crescent shaped, will travel-transverse dune- abunda...
