Sandy. Dry. Hot. These are the words typically used to describe the desert. But the endless, windswept dunes that come to mind only make up a small percentage of the deserts on the planet. A desert is actually just a place that has very little precipitation.
Subtropical deserts like the Sahara are what people generally imagine when they think about the desert. The Sahara has rocky plateaus as well as sand dunes. During the summer, the temperature in the Sahara can reach over 50°C (122°F), making it one of the hottest deserts on Earth. Despite these temperatures, the Sahara is home to olive trees, antelope, jerboa, scorpions, jackals, and hyenas. It is even home to some people, with several major cities located there, including Egypt’s Cairo, Libya’s Tripoli, and Mali’s Timbuktu. At 9.4 million square kilometers(3.6 million square miles), the Sahara is also the largest hot desert on Earth.
The largest desert on Earth is Antarctica, which covers 14.2 million square kilometers(5.5 million square miles). It is also the coldest desert on Earth, even colder than the planet’s other polar desert, the Arctic. Composed of mostly ice flats, Antarctica has reached temperatures as low as -89°C (-128.2°F). The ice that covers the area is on average 2.45 kilometers (1.5 miles) thick. There is almost no vegetation in Antarctica, so the animals that live there are mostly carnivores, such as penguins, albatrosses, whales, and seals. Antarctica’s waters are abundant with sea life, including fish, krill, and sea sponges.
How can both the Sahara and Antarctica be deserts? The reason is that they both see little precipitation during the course of a year, typically around 25 centimeters (10 inches), or less. This makes them both difficult places for plants and animals to live. Both deserts have fossil evidence suggesting that this was not always true. Based on fossil evidence, the Sahara and Antarctica appear to have been the homes of many plants and animals in the past.
Deserts are captivating landscapes, aren't they? It's intriguing how diverse they are beyond the common image of sandy, hot expanses. My background in environmental science and geography has immersed me in the study of various deserts worldwide. Let's break down the concepts from the article to understand these distinct deserts better:
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Desert Definition: Deserts are defined not solely by sand dunes but by the scarcity of precipitation, typically less than 25 centimeters (10 inches) per year. This lack of rainfall limits vegetation and challenges the survival of both plants and animals.
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Types of Deserts: a. Subtropical Deserts: These, like the Sahara, are what most people picture when thinking of deserts. They feature extreme temperatures, reaching over 50°C (122°F) in summer, rocky plateaus, and sand dunes. Despite the harsh conditions, these deserts support diverse life forms, including olive trees, antelope, scorpions, and more.
b. Polar Deserts: Antarctica stands as the largest desert on Earth, even though it's icy and cold. With little precipitation, it meets the desert criteria. Its extreme cold, averaging -89°C (-128.2°F), and minimal vegetation make it a harsh habitat. However, it's home to specific carnivorous animals like penguins, albatrosses, whales, and seals.
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Sahara Desert: It spans 9.4 million square kilometers (3.6 million square miles) and hosts diverse life forms despite its extreme temperatures. Major cities like Cairo, Tripoli, and Timbuktu are situated within its boundaries, showcasing its surprising ability to sustain human habitation.
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Antarctica: Covering 14.2 million square kilometers (5.5 million square miles), Antarctica is the coldest desert on Earth. Its landscape, primarily ice flats averaging 2.45 kilometers (1.5 miles) thick, supports minimal vegetation, leading to an ecosystem dominated by carnivorous animals. The surrounding waters, however, thrive with diverse sea life.
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Fossil Evidence: Both the Sahara and Antarctica bear fossil evidence of a past that contradicts their current barrenness. Fossils reveal that these regions once teemed with various plant and animal life, suggesting a significant environmental change over time.
Understanding these deserts involves considering their climates, geographical features, biodiversity, and the impact of past environmental shifts on their current states. It's a fascinating study of how environments evolve and adapt over time!
