29-09-2016, 09:55 AM
Rain water, also called precipitation, is a natural feature of the earth's weather system. Air currents in the atmosphere bring evaporated water from the ocean and the earth's surface up into the sky. The evaporated liquid condenses in the cold air, forming moisture-filled rain clouds.
Significance
Rain water's most well-known and most important effect is providing you with water to drink. According to the United States Geological Survey, rain water seeps into the ground in a process called infiltration. Some of the water seeps deep beneath the top layers of soil where it fills up the space between subsurface rocks--it becomes ground water, also called the water table. Less than 2 percent of the earth's water is ground water, but it provides 30 percent of our fresh water. Without rain water's continued replenishment of the water table, potable water would become scarcer than it already is.
Process
All clouds are composed of water vapor and particles of moisture, according to the USGS. When those droplets make contact with something solid--such as a particle of dust or smoke--they wrap around the particle and grow larger. Droplets can also collide with other droplets, forming a larger particle with increased weight. When the weight of a droplet causes it to fall faster than the updraft current in the air, it becomes precipitation and falls to earth. The USGS reports that it takes millions of droplets to form one drop of rain water.
Significance
Rain water's most well-known and most important effect is providing you with water to drink. According to the United States Geological Survey, rain water seeps into the ground in a process called infiltration. Some of the water seeps deep beneath the top layers of soil where it fills up the space between subsurface rocks--it becomes ground water, also called the water table. Less than 2 percent of the earth's water is ground water, but it provides 30 percent of our fresh water. Without rain water's continued replenishment of the water table, potable water would become scarcer than it already is.
Process
All clouds are composed of water vapor and particles of moisture, according to the USGS. When those droplets make contact with something solid--such as a particle of dust or smoke--they wrap around the particle and grow larger. Droplets can also collide with other droplets, forming a larger particle with increased weight. When the weight of a droplet causes it to fall faster than the updraft current in the air, it becomes precipitation and falls to earth. The USGS reports that it takes millions of droplets to form one drop of rain water.
