Answer to Question 1Mechanical weathering is dominant because temperatures can fluctuate a great deal in a day and frost
wedging is common in winter. Plant roots and salt crystal growth may also break down some rocks.
Chemical weathering occurs only a little because the land is very arid and few plants mean few organic
acids. Most chemical weathering takes place in winter months when there is more precipitation
Answer to Question 2Deserts are arid lands that receive less than 25 cm of rain per year, have high evaporation rates, have
poorly developed soils, and have low amounts of vegetation. Deserts are found at around 30 north and
south of the equator where descending warm, dry air causes more evaporation than precipitation and
also where large mountain ranges block moisture and cause rain-shadow deserts.