Condensation
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- Condensation occurs when water vapor changes to a liquid.
- For
condensation to take place, the air must be saturated and there must be a
surface on which the vapor can condense.
- In the air above the ground, tiny hygroscopic (water-absorbent) particles known as condensation nuclei serve as the surfaces on which water vapor can condense.
Clouds
Cloud Heights
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FogFog, generally considered an atmospheric hazard, is a cloud with its base at or very near the ground. Fogs formed by cooling include:
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Dew and White Frost
- Dew is the condensation of water vapor on objects that have radiated sufficient heat to lower their temperature below the dew point of the surrounding air.
- White frost forms when the dew point of the air is below freezing.
Precipitation Formation
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For precipitation to form, millions of cloud
droplets must somehow coalesce into drops large enough to sustain themselves
during their descent.
The two mechanisms that have been proposed to explain this phenomenon are:
The two mechanisms that have been proposed to explain this phenomenon are:
- the Berger on process, which produces precipitation from cold clouds (or cold cloud tops) primarily in the middle latitudes, and
- the warm cloud process most associated with the tropics called the collision-coalescence process.
- rain (drops of water that fall from a cloud and have a diameter of at least 0.5 millimeter) and
- snow (precipitation in the form of ice crystals or, more often, aggregates of ice crystals).
- sleet (falling small particles of ice that are clear to translucent)
- glaze (formed when supercooled raindrops turn to ice on colliding with solid objects)
- hail (hard, rounded pellets or irregular lumps of ice produced in large cumulonimbus clouds)
- rime (a deposit of ice crystals formed by the freezing of supercooled fog or cloud droplets on objects whose surface temperature is below freezing).
- drizzle (smaller droplets of rain, yet larger than mist)
- mist (smallest water droplets visible)
- gaupel (watery hail)
FORMS OF PRECIPITATION
Measurement
A Standard Rain Gauge
Rain Measurement
Rain, the most common form of precipitation, is probably the easiest to measure.
The most common instruments used to measure rain are:
Rain, the most common form of precipitation, is probably the easiest to measure.
The most common instruments used to measure rain are:
- the standard rain gauge, which is read directly, and
- the tipping bucket gauge and weighing gauge, both of which record the amount of rain.
- The two most common measurements of snow are depth and water equivalent.
- Although the quantity of water in a given volume of snow is not constant, a general ratio of 10 units of snow to 1 unit of water is often used when exact information is not available.
Effects of Global Warming On Rain
- Even though a warmer planet is expected to bring more precipitation, we humans may not be able to capture enough of it.
- As the climate warms , more water will fall in the form of rain rather than snow, studies have shown. New modeling details how reservoirs will fill earlier than normal, and how snow will melt earlier in the year, altering the timing of runoff that water officials count on in many major reservoir systems.
- "When you change the seasonality of how rivers flow you are essentially putting the water runoff all into spring rather than being able to draw it out through summer," says Tim Barnett of the Scripps Institution of Oceanography. "Mother Nature is not going to act like a reservoir as it has in the past and when the water comes out all at once there isn't enough capacity to contain it."
- Systems that can't hold an entire season of runoff all at once will be challenged to meet the demands of their water customers.
- The idea that Global warming will bring more rain and less snow, goes back to least 1999,when a University of California, Santa Barbara researcher said “There will be too much water at the wrong time and too little when we need it.”
We create problems for our earth now lets provide the solutions to make safer hearth!!