GEOG 001 Lecture Notes - Lecture 21: Evapotranspiration, Darfur, Aggradation
10 Aug 2020
School
Department
Course
Professor
Document Summary
Drought, war and the tragedy of the commons (dafur) Indication of the degree of dryness of the climate. Aridity index- takes into account water loss through evapotranspiration. Rising air and precipitation near equator flow towards poles. Downward arms of hadley cells in mid latitudes (subtropics) are very dry, no clouds- desert regions. Cells circulation in mid regions- gets rid of excess heat from the equator and moves it to the poles. Trade winds converge at itcz- become part of convecting air masses and create doldrums (light winds) in between convection. Production of desert like conditions in arid and sub-humid regions. Factors causing it- overgrazing, vegetation removal, erosion, drought. Not the loss of land to pre-existing deserts as a result of sand movement. Reduction of loss in arid regions- resulting from land use. Deterioration of the physical, chemical and biological or economic properties of soil. Long term loss of natural vegetation, erosion.
