Air conditioning eventually reach the upper atmosphere. Once the refrigerant reaches the stratosphere, UV radiation from the Sun homolytically cleaves the chlorine-carbon bond, yielding a chlorine radical. These chlorine radicals catalyze the breakdown of ozone into diatomic oxygen, depleting the ozone layer that shields the Earth's surface from strong UV radiation. Each chlorine radical remains active as a catalyst until it binds with another radical, forming a stable molecule and quenching the chain reaction. Prior to 1994, most automotive air conditioning systems used R-12 as a refrigerant. It was replaced with R-134a refrigerant, which has no ozone depletion potential. Old R-12 systems
Sun goddess of the Earth Sun goddess of the Earth The Sun goddess of the Earth (Hittite: "taknaš UTU", Luwian: tiyamaššiš Tiwaz) was the Hittite goddess of the underworld. Her Hurrian equivalent was and her Sumerian/Akkadian equivalent was Ereshkigal, both of which had a marked influence on the Hittite goddess from an early date. In the Neo-Hittite period, the Hattian underworld god, Lelwani was also syncretised with her. In Hittite texts she is referred to as the "Queen of the Underworld" and possesses a palace with a vizier and servants. In the Hittite New Kingdom she is attested as the mother of two weather gods.