Editing Cloud physics (section)

=== Collision-coalescence ===
{{main|Coalescence (meteorology)}}
One theory explaining how the behavior of individual droplets in a cloud leads to the formation of precipitation is the collision-coalescence process. Droplets suspended in the air will interact with each other, either by colliding and bouncing off each other or by combining to form a larger droplet. Eventually, the droplets become large enough that they fall to the earth as precipitation. The collision-coalescence process does not make up a significant part of cloud formation, as water droplets have a relatively high surface tension. In addition, the occurrence of collision-coalescence is closely related to entrainment-mixing processes.<ref>{{cite journal |doi=10.1007/s11434-012-5556-6 |title=A method for distinguishing and linking turbulent entrainment mixing and collision-coalescence in stratocumulus clouds |journal=[[Chinese Science Bulletin]] |volume=58 |issue=4–5 |pages=545–51 |year=2012 |last1=Lu |first1=Chunsong |last2=Liu |first2=Yangang |last3=Niu |first3=Shengjie |bibcode=2013ChSBu..58..545L |doi-access=free }}</ref>