Legacy is a term we may hear and see in print from time to time.
According to www.thefreedictionary.com, it means "a gift by will," "something handed down or received from an ancestor or predecessor."
Our predecessors from the 1900s gave us such a legacy. Even as late as 2011, an "unprecedented" ozone hole developed in the Arctic, with continuing ozone holes forming over the Antarctic regions. This was not done on purpose. There was a lack of awareness and understanding about the impact of groups of chemicals, chlorofluorocarbons and hydrofluorocarbons had on the Earth's atmosphere.
These chemicals consist of volatile molecules and are used as refrigerants in our homes, cars and elsewhere in life. When released/leaked into the atmosphere, they rise into the stratosphere high above the Earth's surface, where they react with and destroy the ozone layer.
The chemistry is very complex, but it is clear that by reducing the ozone layer, increased amounts of high-energy solar UV radiation are able to reach the Earth's surface. This radiation is very harmful and can cause skin cancer and have other deleterious effects on life on Earth.
With some incomplete data but ongoing research, scientists sounded the alarm to policy makers, who rose to the challenge. In 1987, the Montreal Protocol was signed by President Ronald Reagan and Margaret Thatcher and came into force Jan. 1, 1989. Altogether, 196 countries have signed the Protocol to limit these and other similar chemicals, and to eventually stop their use. However, the legacy, the gift, stays with us and will for the next half century and more. Until the ozone hole closes, people from Scandinavia to Russia, Canada to Argentina will be at risk.
But what about carbon dioxide? Is there a legacy here as well? A gift from us to future generations?