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The most common chemicals used for cloud seeding include silver iodide and dry ice (frozen carbon dioxide). The expansion of liquid propane into a gas has also been used and can produce ice crystals at higher temperatures than silver iodide. The use of hygroscopic materials, such as salt, is increasing in popularity because of some promising research results.
Seeding of clouds requires that they contain supercooled liquid water-that is, liquid water colder than zero degrees Celsius. Introduction of a substance such as silver iodide, which has a crystalline structure similar to that of ice, will induce freezing nucleation. Dry ice or propane expansion cools the air to such an extent that ice crystals can nucleate spontaneously from the vapor phase. Unlike seeding with silver iodide, this spontaneous nucleation does not require any existing droplets or particles because it produces extremely high vapor supersaturations near the seeding substance. However, the existing droplets are needed for the ice crystals to grow into large enough particles to precipitate out.
In mid-latitude clouds, the usual seeding strategy has been predicated upon the fact that the equilibrium vapor pressure is lower over ice than over water. When ice particles form in supercooled clouds, this fact allows the ice particles to grow at the expense of liquid droplets. If there is sufficient growth, the particles become heavy enough to fall as snow (or, if melting occurs, rain) from clouds that otherwise would produce no precipitation. This process is known as "static" seeding.
Seeding of warm-season or tropical cumulonimbus (convective) clouds seeks to exploit the latent heat released by freezing. This strategy of "dynamic" seeding assumes that the additional latent heat adds buoyancy, strengthens updrafts, ensures more low-level convergence, and ultimately causes rapid growth of properly selected clouds.
Cloud seeding chemicals may be dispersed by aircraft (as in the second figure) or by dispersion devices located on the ground (generators, as in first figure, or canisters fired from anti-aircraft guns or rockets). For release by aircraft, silver iodide flares are ignited and dispersed as an aircraft flies through the inflow of a cloud. When released by devices on the ground, the fine particles are carried downwind and upwards by air currents after release.
An electronic mechanism was tested in 2010, when infrared laser pulses were directed to the air above Berlin by researchers from the University of Geneva.The experimenters posited that the pulses would encourage atmospheric sulfur dioxide and nitrogen dioxide to form particles that would then act as seeds.
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How do you make rain go away?
go to the Eart Science book. The airplanes can drop artificial ice nuclei into a cloud in an effort to produce rain. The other is to "seed" a supercooled cloud by dropping pellets of frozen "dry ice", into it.
Done to induce rain or snow?
Cloud seeding with Silver Iodide.
How do the monsoons help?
by the rain
How do some countries make rain?
Countries don't make rain. Weather does.
What is the immediate cause of most rain?
Seeding clouds with silver iodide or dry ice
How do rainmaker make rain?
The only known way to make rain is by physically seeding clouds, usually with silver iodide and dry ice. Traditional rainmakers do not actually have the ability to make rain.
How do the royal rainmakers of Thailand make rain?
There is no way to make rain without physically seeding clouds, usually with silver iodide and dry ice. Traditional rainmakers do not actually have the ability to make rain.
When was Silver Rain created?
Silver Rain was created on 2005-03-08.
When was The Lonely Silver Rain created?
The Lonely Silver Rain was created in 1985.
When was Silver Rain Radio created?
Silver Rain Radio was created in 1995.
How many pages does The Lonely Silver Rain have?
The Lonely Silver Rain has 231 pages.
What is the ISBN of The Lonely Silver Rain?
The ISBN of The Lonely Silver Rain is 0-394-53899-4.
When using blackra1n where do you find the make it rain button?
please help i need to unlock my i-pod a.s.a.p! and i can't find make it rain anywhere
Which compounds are sprayed over clouds to cause artificial rain?
Silver iodide is the primary compound, but there is nothing that will make it rain without fail, and it won't always do it where you want it.
How do you make rain go away?
go to the Eart Science book. The airplanes can drop artificial ice nuclei into a cloud in an effort to produce rain. The other is to "seed" a supercooled cloud by dropping pellets of frozen "dry ice", into it.
Is there a Pokemon that can help make a egg hatch faster in Pokemon soul silver?
If you have a magmar with you on your team that will help.
Which induce artificial rain?
Silver Iodide
