Ozone layer upper-atmosphere ozone-depletion rate slowed down significantly during the previous decade. Some breakdown can be expected to continue because of ODSs used by nations which have not banned them, and because of gases which are already in the stratosphere. Some ODSs, including CFCs, have very long atmospheric lifetimes, ranging from 50 to over 100 years. It has been estimated that the ozone layer will recover to 1980 levels near the middle of the 21st century. A gradual trend toward "healing" was reported in 2016. Compounds containing C–H bonds (such as hydrochlorofluorocarbons, or HCFCs) have been designed to replace CFCs in certain
The Layer Quaternity and role of the quaternity in religious symbolism is applicable to the Layer Quaternity. To Jung the quaternity was a natural expression of differentiation which always represents a totality, citing the four elements, the four seasons, the ancient Greek schemata of the four humours, and the four temperaments, as well as the four Evangelists with their respective emblems in the form of the tetramorph in Christian iconography, as examples. The symbolism of the four entities of the Layer Quaternity exemplify Jung's observation that individuation develops through psychic qualities consisting of two pairs of opposites, which are often polarised to each