Droughts are caused by changes in land and sea surface temperatures, atmospheric circulation patterns and soil moisture content. A change in any one of these factors sets up a cyclical chain of events that can result in extreme climate conditions such as drought.Continue Reading
Unusual warming or cooling of sea surface temperatures can create a change in air temperature. This change of air temperature can affect the location of convection currents responsible for weather patterns, shifting warmer air over previously cooler locations. Heated air pulls moisture from the soil, allowing it to form clouds and return to the Earth as rain when it enters the cooler upper atmosphere. If weather patterns shift enough to create an area with little rainfall over a period of time, there is not enough moisture in the soil to draw up into the air to create clouds once the weather pattern shifts back to its former location. Moisture continues to be removed from the soil on a daily basis, and no rain clouds are able to form to replace the moisture.
Sustained dry periods can create droughts that cause economic distress across an area. Drought can impact crops, the water supply, stream water quality, recreation, hydropower generation, navigation and forest resources.Learn more about Rain
Areas of high elevation, such as mountain ranges, often drain the air of its moisture. As the air rises up the mountain, it cools. As the air cools, it loses its ability to hold water. The water then condenses out of the air and falls as precipitation.Full Answer >
Cyclonic rainfall, also known as frontal rain, is caused when two air masses of different temperatures meet. Warm air and cool air don´t mix, as they have different densities. As the warm air rises over the heavier cool air, it cools and creates a front; clouds form and produce rain.Full Answer >
Infiltration, as it occurs in the water cycle, is the process by which the water on top of the ground enters into the soil. Infiltration is necessary for the sustaining of plant life. Some of the water not used by plants moves deeper into the ground water level.Full Answer >
The weight of soil varies with its moisture content and density. Per cubic yard, topsoil can weigh 1,700 pounds when dry and 2,400 pounds when damp, with an average weight of 2,000 pounds.Full Answer >