Deserts cover about 20% of the surface of the Earth, and you probably think that you know what a desert is. You think It's a chunk of land that is all covered with sand, and it's very hot there. Right? That's partly right, and partly wrong. A desert is actually a piece of land, no matter hot or cold, that has small amounts of precipitation throughout the year. It usually gets less than 10 inches (25 cm) a year, although the amount does vary from year to year. But all deserts aren't hot. There are actually four kinds of deserts: hot, dry deserts, cold deserts, semiarid deserts, and coastal deserts.
Yes, there is such thing as a cold desert. Cold deserts are located near the Arctic part of the world. For example, Antarctica is one. Very few plants or animals can survive there. And as a result, only a few people live there. The only people that live in cold deserts are scientists. These deserts have fairly long, cold winters with snow and short, moist, moderately warm summers. The average winter temperature is between -2 to 4° C , and the average summer temperature is between 21-26° C. The average annual precipitation ranges from 15-26 cm. There are no animals from a cold desert area in the Brandywine Zoo.
Most hot and dry deserts are located near the Tropic of Cancer or the Tropic of Capricorn. As their name indicates, they are hot and they are dry. Hot and dry deserts' temperatures range from 20 to 25° C. Summer temperatures in these deserts often reach 100 degrees Fahrenheit or higher. At night the temperature may drop to 45 degrees Fahrenheit or lower.They usually have very little rainfall and/or they get a lot of rainfall in a very short time, and then there are long periods of time (especially the winter) when there is no rain.The average rainfall is usually less than 15 cm a year. There is not much vegetation. The plants that do live there have special adaptations that let them survive the hot temperatures and store water when there is little rain. Animals that live in the desert are rarely active during the day because of the heat. They hide out under rocks or in burrows. They usually move around at night or around dusk or dawn. Often they are light-colored so they will blend in with their surroundings.
When talking about semiarid deserts, people are referring to deserts like the sagebrush deserts of Utah, Montana and the Great Basin, and similar areas located in Newfoundland, Greenland, Russia, Europe and northern Asia. In these deserts the summers are moderately long and dry, and like hot deserts, the winters normally bring little rainfall. Summer temperatures usually average between 21-27° C. It normally does not go above 38° C . Also, like the hot desert, rainfall is often very low and/or concentrated. The average rainfall ranges from 2-4 cm yearly. However, the evening temperatures in these deserts are cool, around 10° C , and because the nights are cool, condensation occurs. Dew is formed, and the amount of dew formed may equal or exceed the rainfall received by some deserts. Many of the plants in a semiarid desert have spines and silvery or glossy leaves that let them reflect more radiant energy. Many of the animals live in underground burrows. What animal at the Brandywine Zoo lives in an underground burrow?
Coastal deserts are found in moderately cool to warm areas such as the Nearctic and Neotropical realm. A good example is the Atacama of Chile. Coastal deserts have cool winters and moderately long, warm summers. The average summer temperature ranges from 13-24° C. Winter temperatures are 5° C or below. The average rainfall measures 8-13 cm in many areas.
back to Where in the World
back to Activities