How does climate influence hot deserts?

Climate influences hot deserts by creating extremely arid conditions with high temperatures and minimal rainfall, shaping their unique ecosystems.

Hot deserts are characterised by their extreme aridity, which means they receive very little rainfall, often less than 250 millimetres per year. This lack of precipitation is primarily due to their location in subtropical high-pressure zones, where descending air inhibits cloud formation and precipitation. These high-pressure systems are typically found between 20° and 30° north and south of the equator, such as the Sahara Desert in Africa and the Arabian Desert in the Middle East.

Temperatures in hot deserts can be extreme, often exceeding 40°C during the day. The intense heat is a result of the clear skies and strong solar radiation, which heats the ground quickly. At night, however, temperatures can drop dramatically because the lack of cloud cover allows heat to escape rapidly into the atmosphere. This significant temperature variation between day and night is a defining feature of hot desert climates.

The arid conditions and extreme temperatures have a profound impact on the desert ecosystem. Plants and animals in hot deserts have evolved unique adaptations to survive. For example, many desert plants, like cacti, have thick, fleshy stems that store water, and spines instead of leaves to reduce water loss. Animals, such as the fennec fox, have large ears to dissipate heat and are often nocturnal to avoid the daytime heat.

Soil in hot deserts is typically sandy or rocky and lacks organic matter due to the sparse vegetation. This makes it difficult for plants to grow, further contributing to the barren landscape. When rain does fall, it often comes in short, intense bursts, leading to flash floods that can quickly erode the landscape.

In summary, the climate of hot deserts, characterised by high temperatures and minimal rainfall, creates challenging conditions that shape the unique flora, fauna, and landscapes found in these regions.