Late Axon, age 11, of Salt Lake City, Utah, for his question:
How hot and cold does it get in the Sahara?
The deserts on Mars are larger and colder but our great Sahara gets a eat deal hotter. then the midsummer sun beats down on its sandy dunes, the temperature nay soar to 130 degrees Fahrenheit. During the summer night, the deserts temperature often drops swiftly. In winter, frost comes to large areas in the Sahara and some of its mountain peaks are capped with snow.
The great Sahara is the biggest, the hottest, but not quite the coldest desert on the earth. It covers over three million square miles which is almost as big as Canada. One would expect to find a variety of scenery in such an enormous area, with a variety of temperatures.
Some parts of the great desert are covered with parched sandy dunes. Other georaphical features include barren hills and plateaus, rocky mountain ranges and vast stretches of loose gravel. This whole region of North Africa is an arid desert because the prevailing trade winds that blow across it bring few clouds and little moisture.
Hence, the big blue sky above it is usually clear and the air is drier than dry. This allows the summer sun to beat down the blazing heat. Then the sandy surface gets much hotter than the air above it. The mid day temperatures often reach 120 and sometimes 130 decrees Fahrenheit. The record is held by a place called Azizia in the desert, which is one of the Sahara's hot spots. One day, the official temperature there soared to 135.4 degrees in the shade.
Some people claim that California's Death Valley gets to be the hottest spot on earth. There the record for July 10, 1913 was 134 degrees F. This was tops for North America, but more than two degrees cooler than the Sahara's known record. However, Death Valley's normal temperatures often reach 125 degrees, which is hotter than many summer days in the Sahara.
The same clear blue skies that bring,, down heat from the blazing sun also let the earth's heat escape during the night. After a seething day of 120 degrees, temperatures in the Sahara often plummets down to 70 degrees or lower. People who live there must prepare for the sudden changes. The desert animals must be adjusted to the sharp contrasts of day and night temperature.
The Wide Sahara straddles the Tropic of Cancer, where winters tend to be mild. But cold dry winds often bring frosty temperatures of 30 degrees to some of the low lying, regions. Things are colder on the desert plateaus, 2,000 feet above sea level. The highest peaks are 6,000 to 10,000 feet and sometimes they are covered with winter snows for many days at a time.
Only parts of the great desert are desolate wastelands. Even these are crossed by caravan routes and along the way there are towns where the travelers pause to rest and trade. And here and there throughout the great desert there are oases, where pockets of ground water nourish green spots of thriving vegetation. Here the plants give off moisture and tend to lessen both the heat and the cold.