When rain falls on desert soils, it can quickly surpass the infiltration capacity of the soil, leading to the formation of ephemeral rivers and arroyos. These channels can transport large amounts of water and sediment as they flow through desert landscapes.

Erosion and sediment transport.

The high velocity of water in ephemeral rivers and arroyos can cause significant erosion and transport of sediment. This can result in the formation of gullies, canyons, and other erosional features. Sediment can also be transported downstream, where it can accumulate in river deltas and playas, or be carried out to sea.

Infiltration and groundwater recharge.

Some of the rain that falls on desert soils may infiltrate the ground and recharge groundwater aquifers. This is an important process because groundwater is a valuable water resource in desert environments.

Plant growth.

Rain can also support plant growth in deserts, even if it only rains occasionally. Desert plants have evolved various adaptations to survive in these environments, such as deep root systems and the ability to store water. When rain falls, these plants can take up water and nutrients from the soil, which helps them to grow and reproduce.

Flash flooding.

In some cases, heavy rains can lead to flash flooding in desert areas. Flash floods can be very dangerous and can cause significant damage to infrastructure and property.

The updated model developed by researchers at the University of Arizona provides a more detailed and accurate understanding of how rain falls on desert soils and the resulting processes that occur. This information can be used to better manage water resources and mitigate the impacts of flooding in desert environments.