A Level>Notes>Physical geography>Hot desert systems and landscapes

Desert Systems

: Deserts are open systems- generally in dynamic equilibrium Inputs: Water enters the system through infrequent rainstorms. Sediment can be carried into a desert system by wind or water. Energy: Insolation = the solar radiation that reaches the Earth Insolation is...

read more

Deserts- Distribution and Characteristics

Aridity Index: Water balance = relationship between mean annual precipitaion (P) and potential evapotranspiration (PET). If P>PET = water surplus, vice versa = water deficit. In deserts, P<PET (water deficit). The size of the deficit (difference between P and...

read more

Processes in Hot Deserts

Mechanical weathering: Rock is physically broken into smaller pieces in situ. Thermal fracture: Extreme temperatures in deserts (0-50OC desert air can't block sunlight or trap heat) During the day (when it's hot) rock expand and at night (when it's cold) they...

read more

Landforms in Hot Deserts

FLUVIAL EROSION NAME DESCRIPTION DIAGRAM EXAMPLE Pediments Pediments are desert plains - gently sloping areas of rock (usually covered in a thin layer of debris). They're formed by the erosion of rock by sediment carried in sheet floods or small streams.    ...

read more

Hot Desert Environment- Case Study

Introduction: Northern Africa across tropic of Cancer 6km2 across 10 countries   Characteristics: Climate: Air circulation causing little moisture over tropics & high pressure of descending air Rainfall: Less than 100mm annual rainfall - mainly via...

read more

Desertification

The degradation of land in arid areas by which fertile land becomes desert like 75 billion tonnes of soil eroded annually   Human Causes: Overgrazing Reduces vegetation > soil erosion (due to lack of plant roots) Trampling by animals > compressed &...

read more