Few landforms have proven origins. Many landforms can come about through different processes and quite different conditions, e. Skip to main content. Search form. Sign up Log in. Title Desert Features created by Water. Quick revise Rain does fall occasionally in deserts, and desert storms are often violent. More people drown in deserts than die of thirst! Sabkhas — an occasionally flooded desert area with an extensive thickness of evaporates salts , usually coastal in nature.
Duricrust — hardened areas of minerals that cover deserts. They are impermeable and thought to be due to weathering. The term wadi comes from both the Arabic and Hebrew languages. Specifically, it refers to a dry riverbed that contains water during rainy seasons and is located in a valley-like area of the desert.
Wadis are generally located in the flat or slightly rolling areas of deserts and often leads to dry lakes as well. A wadi can be recognized by its braided appearance, which is caused by a lack of constant water flow and an excess of sediment build-up. Sometimes, this sediment may collect in significant amounts, blocking water flow and effectively changing the direction of seasonal rivers. In addition to the low water levels, wind also affects sediment buildup by bringing in dry sands that collect on top of moist sand.
The bottoms of wadis are often covered in sand and loose gravel. The lower levels of this sediment are often packed very densely. This means that during rainy season, water is not quickly absorbed by the ground and has nowhere to drain, resulting in rapid flooding. Flash flooding in wadis is made even more dangerous because of the previously mentioned directional changes, which can send waters into communities unexpectedly.
Desert lakes are generally shallow, temporary, and salty. Because these lakes are shallow and have a low bottom gradient, wind stress may cause the lake waters to move over many square kilometers.
When small lakes dry up, they leave a salt crust or hardpan. That's because temperatures in the Sahara can plummet once the sun sets, from an average high of degrees Fahrenheit 38 degrees Celsius during the day to an average low of 25 degrees Fahrenheit minus 4 degrees Celsius during the night, according to NASA. Death Valley holds the record for the highest air temperature on the planet: On 10 July , temperatures at the aptly named Furnace Creek area in the California desert reached a blistering The high position of the Sun, the extremely low relative humidity, and the lack of vegetation and rainfall make the Great Desert the hottest large region in the world , and the hottest place on Earth during summer in some spots.
Why are wadis formed? Asked by: Amy Gislason. What is the climate like in the Sahara? Is it safe to drink from an oasis? Why are wadis so important for human life? What does wadi Rum mean in English? What are examples of wadis? What does wadi mean in Jordan? What is a dried up river called?
What is Wadi in the Bible? What is the Wadi of Egypt? Why is wadi important? How are the wadis formed in UAE? Which wadi flows into the Red Sea?
0コメント