Editing Cloud albedo (section)

== Influence on global climate ==
Cloud albedo indirectly affects global climate through solar radiation [[scattering]] and [[Absorption (electromagnetic radiation)|absorption]] in Earth's radiation budget.<ref name=":12" /> Variations in cloud albedo cause atmospheric instability that influences the [[hydrological cycle]], weather patterns, and [[atmospheric circulation]].<ref name=":22" /> These effects are parameterized by [[Cloud forcing|cloud radiative forcing]], a measure of short-wave and long-wave radiation in relation to [[cloud cover]]. The [[Earth Radiation Budget Experiment]] demonstrated that small variations in cloud coverage, structure, altitude, droplet size, and phase have significant effects on the climate. A five percent increase in short-wave reflection from clouds would counteract the greenhouse effect of the past two-hundred years.<ref name=":22" />

=== Cloud albedo-climate feedback loops ===
There are a variety of positive and negative [[Cloud feedback|cloud albedo-climate feedback loops]] in cloud and climate models. An example of a negative cloud-climate feedback loop is that as a planet warms, cloudiness increases, which increases a planet's albedo. An increase in albedo reduces absorbed solar radiation and leads to cooling. A counteracting positive feedback loop considers the rising of the high cloud layer, reduction in the vertical distribution of cloudiness, and decreased albedo.<ref>{{Cite journal|last1=Wetherald|first1=R. T.|last2=Manabe|first2=S.|date=1988|title=Cloud Feedback Processes in a General Circulation Model|journal=Journal of the Atmospheric Sciences|language=EN|volume=45|issue=8|pages=1397–1416|doi=10.1175/1520-0469(1988)045<1397:CFPIAG>2.0.CO;2 |bibcode=1988JAtS...45.1397W |issn=0022-4928|doi-access=free}}</ref>

[[Air pollution]] can result in variation in cloud condensation nuclei, creating a feedback loop that influences atmospheric temperature, relative humility, and cloud formation depending on cloud and regional characteristics. For example, increased [[Sulfate aerosol|sulfate aerosols]] can reduce precipitation efficiency, resulting in a positive feedback loop in which decreased precipitation efficiency increases aerosol atmospheric longevity.<ref name=":03" /> On the other hand, a negative feedback loop can be established in mixed-phase clouds in which [[black carbon]] aerosol can increase ice phase precipitation formation and reduce aerosol concentrations.<ref name=":03" />