Polar Stratospheric Cloud

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This morning we’ve once again seen the Polar Stratospheric Cloud in the sky above (also called the Nacreous or Mother of Pearl Cloud).

There are two main types of the PSC, depending on their chemical compositon. Type I clouds (of which there are three sub-types) contain water, nitric acid and sulfuric acid, and are implicated in the ozone depletion. Type II contain water only.