A student studies that a few factors affect the processes of water cycle. The water cycle in region A and B is disturbed such that the amount of
precipitation increased sharply in region B, whereas it decreased considerably in region A. Which option correctly identifies the likely
calamity to strike in both the regions? *
Answers
Answer:
The air is full of water, even if you can't see it. Higher in the sky where it is colder than at the land surface, invisible water vapor condenses into tiny liquid water droplets—clouds. When the cloud droplets combine to form heavier cloud drops which can no longer "float" in the surrounding air, it can start to rain, snow, and hail... all forms of precipitation, the superhighway moving water from the sky to the Earth's surface.
Note: This section of the Water Science School discusses the Earth's "natural" water cycle without human interference.
• Water Science School HOME • Water Basics topics • The Water Cycle •
Water cycle components » Atmosphere · Condensation · Evaporation · Evapotranspiration · Freshwater lakes and rivers · Groundwater flow · Groundwater storage · Ice and snow · Infiltration · Oceans · Precipitation · Snowmelt · Springs · Streamflow · Sublimation · Surface runoff
Precipitation and the Water Cycle
Precipitation is water released from clouds in the form of rain, freezing rain, sleet, snow, or hail. It is the primary connection in the water cycle that provides for the delivery of atmospheric water to the Earth. Most precipitation falls as rain.
How do raindrops form?
A rainstorm in the Colorado mountains
A localized heavy summer rainstorm in Colorado, USA.
Credit: Howard Perlman, USGS
The clouds floating overhead contain water vapor and cloud droplets, which are small drops of condensed water. These droplets are way too small to fall as precipitation, but they are large enough to form visible clouds. Water is continually evaporating and condensing in the sky. If you look closely at a cloud you can see some parts disappearing (evaporating) while other parts are growing (condensation). Most of the condensed water in clouds does not fall as precipitation because their fall speed is not large enough to overcome updrafts which support the clouds.
For precipitation to happen, first tiny water droplets must condense on even tinier dust, salt, or smoke particles, which act as a nucleus. Water droplets may grow as a result of additional condensation of water vapor when the particles collide. If enough collisions occur to produce a droplet with a fall velocity which exceeds the cloud updraft speed, then it will fall out of the cloud as precipitation. This is not a trivial task since millions of cloud droplets are required to produce a single raindrop. A more efficient mechanism (known as the Bergeron-Findeisen process) for producing a precipitation-sized drop is through a process which leads to the rapid growth of ice crystals at the expense of the water vapor present in a cloud. These crystals may fall as snow, or melt and fall as rain.
How much water falls during a storm
You might be surprised at the number of gallons of water that fall from the sky in even a small but intense storm. One inch of rain falling on just a single acre results in 27,154 gallons of water on the landscape. If you'd like to know how much water falls during a storm, use our Interactive Rainfall Calculator (English units or Metric units) to find out - you just enter an area size and rainfall amount and see how many gallons of water reach the ground.
