cloud condensation nuclei
Quick Summary
Cloud condensation nuclei are tiny particles suspended in the atmosphere that act as surfaces for water vapor to condense upon, initiating the formation of cloud droplets and ice crystals. Without these nuclei, water vapor requires much higher humidity levels (supersaturation) to transform into liquid water or ice.12
These aerosols, produced by both natural processes and human activities, reduce the supersaturation needed for phase changes. Larger and more soluble aerosols are more effective condensation nuclei. Common examples include sodium chloride and ammonium sulfate. These nuclei are crucial for cloud formation, with their concentration varying based on location and pollution levels.1
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atmosphereCondensationThe concentration of cloud condensation nuclei in the lower troposphere at a supersaturation of 1 percent ranges from about 100 per cubic centimetre (approximately 1,600 per cubic inch) in size in oceanic air to 500 per cubic centimetre (8,000 per cubic inch) in the atmosphere over a continent.…
Read MoreThe concentration of cloud condensation nuclei in the lower troposphere at a supersaturation of 1 percent ranges from about 100 per cubic centimetre (approximately 1,600 per cubic inch) in size in oceanic air to 500 per cubic centimetre (8,000 per cubic inch) in the atmosphere over a continent.…
Read More- atmosphereCondensation
Examples of cloud condensation nuclei include sodium chloride (NaCl) and ammonium sulfate ([NH4]2 SO2), whereas the clay mineral kaolinite is an example of an ice nuclei. In addition, naturally occurring bacteria found in decayed leaf litter can serve as ice nuclei at temperatures of less than about…
Read MoreExamples of cloud condensation nuclei include sodium chloride (NaCl) and ammonium sulfate ([NH4]2 SO2), whereas the clay mineral kaolinite is an example of an ice nuclei. In addition, naturally occurring bacteria found in decayed leaf litter can serve as ice nuclei at temperatures of less than about…
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- climateCloud condensation nuclei
The formation and subsequent freezing of cloud droplets depend on the presence of cloud condensation nuclei and ice nuclei, respectively. Significantly, the biosphere is a major source of both of these kinds of nuclei. Over the continents, condensation nuclei are readily available…
Read MoreThe formation and subsequent freezing of cloud droplets depend on the presence of cloud condensation nuclei and ice nuclei, respectively. Significantly, the biosphere is a major source of both of these kinds of nuclei. Over the continents, condensation nuclei are readily available…
Read More - climateBiogenic ice nuclei
As water vapour condenses onto condensation nuclei, the droplets grow in size. Growth proceeds at relative humidity as low as 70 percent, but the rate of growth is very slow. Growth by condensation is most rapid where the air is slightly supersaturated with water vapour. At this point, cloud droplets…
Read MoreAs water vapour condenses onto condensation nuclei, the droplets grow in size. Growth proceeds at relative humidity as low as 70 percent, but the rate of growth is very slow. Growth by condensation is most rapid where the air is slightly supersaturated with water vapour. At this point, cloud droplets…
Read More