Clous form when the dewpoint of water is reached in the presence of condensation nuclei in the troposphere. Atmosphere is a dynamic system, and the local conditions of turbulence, uplift and other parameters give rise to many types of clouds. Various types of clouds occur frequently enough to have acquired a name of their own, often these are further specified with additional descriptive name. Furthermore, some atmospheric processes can make the clouds organize in distinct patterns such as 'wave cloud' or 'actinoform cloud', these are large scale structures and not always readily identifiable from single point of view.