Investigating Earth's Desert, Grassland, and Rainforest Biomes

Investigating Earth's Desert, Grassland, and Rainforest Biomes — page 7
INVESTIGATING EARTH'S DESERT GRASSLAND AND RAINFOREST BIOMES and the temperature and amount of sunshine all play a role Some definitions of deserts focus on the imbalance between the amount of precipitation received and the amount of moisture that could be lost through evapo ration and through plants leaves In the Sonoran Desert in the southwestern United States and Mexico for example a year's potential evaporation the amount of evap oration that would occur if water were always present is some 100 inches 250 centime ters This is about 20 times the actual annual rainfall Rainfall in deserts is not only scanty but also erratic Most deserts have at least a few days of rain a year but some may get no rain at all for several years or receive a year's amount in one storm For example Iquique in northern Chile had no rain for four years The fifth year brought 0 6 inch 1 5 centime ters making a five year average of 0 12 inch 0 3 centimeter At another time 2 5 inches 6 4 centimeters fell in a single shower Temperatures range widely in deserts In hot deserts daytime air temperatures can regularly exceed 100°F 38° C in summer Al Aziziyah Libya holds the record for the hottest temperature with a high of 136° F 57 8° C while Death Valley Calif comes