Little Bits of History

Oh, No – O-Three

Posted in History by patriciahysell on January 29, 2010

Earth and the atmospheric layers

January 29, 1978: Sweden is the first nation to institute a ban on aerosol sprays citing harm to the ozone layer. Aerosols are a canister containing liquid under pressure which is dissolved with a propellant of compressed gas. The droplets of the propellant quickly evaporates after spraying. The idea for an aerosol goes back to about 1790. However the first aerosol can was invented in Oslo by Erik Rotheim on November 23, 1927. The patent was sold to the US for 100,000 Norwegian kroner. By 1939 a patent was granted for a disposable aerosol can but was not put into widespread use until 1941.

Different types of gasses can be used as the propellant. The problem gas, the one that depletes the ozone layer, is a group of gases called chlorofluorocarbons [CFCs]. Since the Montreal Protocol came into force in 1989, CFCs have been replaced with hydrocarbons which are flammable, nitrous oxide used in food or hydrofluroralkanes used in medicinal sprays.

The ozone layer is a part of the Earth’s atmosphere which contains relatively high concentrations [a few parts per million, which is much higher than at lower atmosphere levels] of ozone – 03. This layer of the atmosphere is responsible for absorbing most of the ultraviolet light sent our way from the sun. Between 93 and 99% of the light rays are absorbed in this lower portion of the stratosphere, located between six and 31 miles above the Earth’s surface. Ultraviolet light isn’t all bad and we need some to help produce Vitamin D. Too much of this type of light can cause ill effect to the immune system and damage skin and eyes.

On August 2, 2003 scientists announced that the worldwide ban of CFCs and other chemical compounds that were thought to be the cause of the hole in the ozone layer has been successful. They stated that the depletion of the layer may be slowing down.

“Thank God men cannot fly, and lay waste the sky as well as the earth.” – Henry David Thoreau

“I’m not an environmentalist.  I’m an Earth warrior.” – Darryl Cherney

“Oh Beautiful for smoggy skies, insecticided grain,
For strip-mined mountain’s majesty above the asphalt plain.
America, America, man sheds his waste on thee,
And hides the pines with billboard signs, from sea to oily sea.” – George Carlin

“Civilization… wrecks the planet from seafloor to stratosphere.” – Richard Bach

Also on this day, in 1856 Queen Victoria established the Victoria Cross.