Hot deserts key terms Flashcards
Desert
An arid environment receiving low levels of precipitation
Aridity index
Ratio between the precipitation and the potential evapotranspiration
Arid
Less than 250mm annual precipitation
Semi-arid
250-500mm annual precipitation
Hyper-arid
An aridity index less than 0.05
Diurnal range
The difference between the daytime and nighttime temperatures
Insolation
The incoming solar radiation that reaches the earth’s surface
Aridisols
An order of soils including infertile alkaline & saline soils of desert areas characterised by accumulations of mineral salt at or near the surface
Sierozems
Darker soils with the presence of some organic material developing below ‘desert shrub’
Raw mineral soils
Course soils that are often rocky due to physical weathering, tending to be slightly alkaline and unproductive
Leaching
When there is little downward movement of minerals in the soil
Sand sea
Areas of deserts that are constantly mobile
Primary productivity
The rate at which energy is converted to organic substances by photosynthetic producers
Xerophytes
A plant that has adapted to survive with very little water
Phereophytes
A plant with a deep root system that draws its water supply from a nearby water table
Ephemerals
A plant with a very short life span
Halophytes
A plant that has adapted to grow in saline conditions
Continentality
The impact of increasing distance from the coast on the climate of an area
Relief rainfall
The rainfall caused by the forced condensation of moist air at a mountain
Fluvial sediment
Sediment that is deposited by rivers
Aeolian sediment (loess)
Sediment that is transported (as loess) and deposited by the wind
Rain shadow
If moist air meets a range of mountains, it is forced to rise, leading to cooling, condensation, cloud formation, and relief rain, which then drops on the other side causing a decline in relative humidity
