These then react with the ozone molecules, resulting in their removal. CFCs have a lifetime in the atmosphere of about 20 to 100 years, and consequently one free chlorine atom from a CFC molecule can do a lot of damage, destroying ozone molecules for a long time.
exists and is an alternate of . In the northern hemisphere of Earth, Fall begins on the Autumnal equinox (22-23 September) (in Persian calender it will begin at the first day of Mehr) and ends on the Winter solstice (21-22 December). In the southern hemisphere of Earth, Fall begins on the Autumnal equinox (20-21 March) and ends on the Winter solstice (20-21 June).
When does spring officially start? How do we define the seasons? It depends on whether you are referring to the astronomical or meteorological spring. When we talk about the beginning of winter or any other season, we are usually talking about the day in our calendars that mark this date. This refers to the astronomical seasons which are a result of the Earth's axis and orbit around the sun.