Do you know what a desert is? Did you know that a desert can be extremely cold and covered in snow? Read on to learn more fascinating facts about Earth’s driest ecosystem.
A Desert: The Driest Ecosystem
Have you ever been to a desert? What was the first thing you noticed? Maybe that it’s hot? Or that there are few plants compared to a forest or a meadow? If you noticed that it was dry, you observed the defining characteristic of a desert. In fact, you might be surprised to hear that a desert doesn’t have to be hot. Some are very cold. A desert is defined as any area that gets less than ten inches of rainfall per year.
Deserts Are Home to Extremes
Deserts are extremely dry, by definition. For example, consider the desert city of Palm Springs, California.
It gets an average of about five and a half inches of rain each year. On the other hand, Miami in subtropical South Florida gets nearly 62 inches of rain every year. That’s a significant difference.Another desert extreme is temperature. You probably think of deserts as being hot, and many are. Being hot is not a requirement for being a desert, though.
Many of the Earth’s deserts are extremely cold. The Sahara Desert in North Africa is the world’s biggest hot desert. Daytime temperatures there can reach up to 122 degrees Fahrenheit. Antarctica is considered a desert because of the lack of rainfall, and reaches extreme low temperatures.
Hot deserts even have extreme changes in temperature over the course of one day. Because there is little water in the desert, the heat absorbed by rocks and dirt during the day in a desert is quickly released once the sun goes down. This means that you can be unbearably hot during the day, but need a winter coat at night to keep warm.
Deserts Are Varied
Television shows and movies tend to give us a uniform picture of what a desert looks like: sand dunes as far as the eye can see, or rugged buttes punctuated by a few cacti. In reality, deserts are diverse. Antarctica is the world’s largest desert; in some places it is totally snow covered, while in others it is rocky and covered with lichen.Hot deserts may be nothing but dunes, but they can also be mountainous and at a high altitude.
For instance, the Atacama Desert extends from the western coast of South America up into the high reaches of the Andes Mountains. Many deserts include scrubby brush and cacti, like the Sonoran Desert of the Southwestern U.S. Here you will find animals ranging from coyotes to wild pigs, a number of bird species, and small deer.
Because of the dryness of the climate and the extreme temperatures, deserts contain less diversity of life forms than other ecosystems.
This is not to say that animals and plants can’t live in deserts; many can. Those that do survive in these locations, like lizards and cacti, are well-adapted to the harsh environment of a desert.Plants living in deserts need to be able to store water for long periods of drought. Cacti and succulents are common types of plants in deserts for this reason.
Animals can be adapted in a number of ways to survive the extreme environment. In hot deserts, many animals are nocturnal, meaning they have adapted the ability to hunt or forage at night to avoid the hot daytime temperatures. Others have developed the ability to burrow underground to avoid the sun and heat. Camels, like cacti, can store water for dry times.
Deserts Are Changeable
Because deserts have little vegetation or plant life, they are susceptible to erosion, or the process by which earth is worn away. This changes the surface of the land more so than in other types of ecosystems.
In other ecosystems, the roots of trees, shrubs, and grasses hold soil in place, slowing the erosion process. Leaves and branches protect the ground from wind weathering.The best example of the changeability of the desert is the sand dune, or a hill of sand created by the flow of water or wind. Not all deserts have sand dunes, but those that do are constantly shifting, and the landscape is always different. Some deserts that have sand dunes include the Sahara in Africa, Death Valley in California, and the Gobi in Asia.
Dunes form when sand piles up due to the blowing of wind. There are a number of different shapes that they can take, such as the barchan dune, which has a crescent shape.Climate change and human activity are changing Earth’s ecosystems, and deserts are no exception. In some locations, ecosystems are becoming more desert-like through a process called desertification, which makes dry land become more arid.
Human activities like farming as well as climate change can cause an arid ecosystem to become even drier.Climate change and increasing worldwide temperatures also impact deserts. As temperatures go up and landscapes lose even more moisture, wildfires become more likely. These fires kill slow-growing trees and cacti adapted to desert living. They are replaced by fast-growing grasses, and the change alters the landscape. Deserts are an important type of Earth ecosystem and one that we should protect in order to protect the diversity of life and to be able to study and enjoy them.
A desert is any location on Earth that receives less than ten inches of rain per year.
Deserts are extremely dry and may be either very hot or very cold. Hot deserts are extremely hot during the day and cold at night.There are many different kinds of deserts, including polar deserts, those with dunes, mountainous deserts, and deserts with diverse plant and animal life. Because plants are limited in deserts, erosion and weathering processes change the landscape easily.
Dunes are a good example of how a desert can change constantly.Human activity is causing more of Earth to become desert through a process called desertification, while climate change is altering current deserts by causing more wildfires.