Sunday 15 September 2013

The British Scientists Who Discovered the Ozone Hole

The British Scientists Who Discovered the Ozone Hole

Author: Susan Hunt MA - Updated: 17 September 2012 
The British Scientists Who Discovered The Ozone Hole
British Antarctic Survey Scientists Who Discovered The Ozone Hole
For more than half a century, the British Antarctic Survey has been taking measurements at the North Pole.
One of the world’s foremost environmental research organisations, it first began taking atmospheric readings in the Antarctic in the 1950s and in 1985, BAS scientists announced the discovery of the Ozone Hole.

Announcement That Changed The World

The researchers involved, Joe Farman, Brian Gardiner and Jonathan Shanklin, published their earth-shattering discovery in the journal, Nature, and it was instrumental in the introduction of the Montreal Protocol banning CFCs.Measurements at Halley station originally began in a bid to understand more about the way ozone absorbs solar energy and, according to rumour, the scientists believed their instruments were faulty when they first discovered the existence of the Ozone Hole.
Scientists in America say that NASA actually discovered the hole before the British Antarctic Survey but believed that its measurements must be incorrect, until they were confirmed by the Survey scientists.

British Antarctic Survey

Currently, more than 400 people work for BAS. It has three stations in the Antarctic, including Halley, as well as two stations on South Georgia. The present station at Halley is made up of a collection of buildings on steel legs, which have to be jacked up every year to keep them clear of snow. Four previous stations all had to be abandoned within a decade after being crushed by ice.
Despite the atrocious conditions, Halley is in operation all year round and is staffed by around 70 people in the summer and 16 in winter. However, very few of the winter staff are scientists – the main staff housed there are those with the technical skills needed to keep the station, its personnel and its experiments running, such as a doctor, mechanics, a cook and a heating engineer.

Darkness For Months

A major event in the Halley calendar is sundown, which marks the last day that the sun will rise over the horizon until winter ends. The base is then plunged into permanent darkness for more than 100 days until the sun eventually returns. Sundown is marked by various events and parties and, traditionally, the winter staff streak around the outside of the base (although they are allowed to wear a hat, gloves and boots).

Halley’s Excellent Location

The base at Halley is an excellent location for studying the atmosphere and ozone depletion, and it has provided an unbroken record of readings since the first data was gathered there in 1956.Its data is sent to forecasting stations to help with weather predictions, and Halley’s climate database is also used by researchers investigating climate change.

Southern Lights

Its position at the edge of the auroral zone, where the Southern Lights are visible in the winter sky, makes it an excellent location for research into Geospace – the region of space where the solar atmosphere interacts with the magnetic field of the Earth.
Following their discovery of the Ozone Hole, Farman, Gardiner and Shanklin received the Society of Chemical Industry (SCI) Environment Medal, reserved for those who have achieved the highest distinction in environmental science.

The Ozone Layer is a vital component in the history of life on earth.
Without it, mankind and most forms of life that we know today probably wouldn’t exist and the environment of the planet would be extremely different.
Hundreds of millions of years ago, only single cell organisms existed on Earth and at that time, the planet lacked the oxygen that we need to live.
But as these organisms evolved, they began to release tiny amounts of oxygen through photosynthesis and over a period of millions of years, this led to the creation of the Ozone Layer.

Identification of Ozone – 03

Ozone is first thought to have been identified in 1839 by Christian Schonbein, a Swiss chemist who was actually looking at electrical discharges. (Ozone can easily be produced by a high voltage electrical arc such as a spark plug or an arc welder). He named it ozone, from the Greek term “to smell”, because of its strong odour (which has been likened to the smell of burning electrical wires).
Schonbein wasn’t able to describe the molecular structure of ozone but this was achieved by Jean-Luis Soret in the 1860s. However, Schonbein continued his research and was one of the first people to suggest that higher concentrations of ozone at ground level could affect people’s health. As history has shown, he was correct in his assumption – ozone is now known to be a main ingredient of today’s city smog.

Ozone link to UV levels

About 40 years after Schonbein’s naming of ozone, researchers examining the amount of UV radiation that reaches Earth discovered a sharp cut off point in the atmosphere – and correctly deduced that this cut off was because of ozone in the upper atmosphere. However, French scientists Charles Farby and Henri Buisson are credited with actual discovery of the Ozone Layer in 1913. They carried out the first measurements of ozone in Europe and in 1920, GMB Dobson, a lecturer in meteorology at Oxford University decided to follow their example.

Vital Ozone Research Carried out in Britain

Dobson went on to research ozone for the next 40 years and was involved in the setting up of special stations around the globe to measure ozone. Frustrated by the equipment available to measure it, he also designed his own instrument. In the 1930s, British physicist, Sidney Chapman, produced a theory explaining how ozone is created and destroyed in the stratosphere and this process became known as Chapman Reactions.
He established that when oxygen molecules in the stratosphere are hit by radiation from the sun, they can split into two oxygen atoms. When one of these separated atoms becomes attached to a complete oxygen molecule, it becomes ozone (O3 ). In later years, scientists realised that Chapman’s theory was incomplete and further research was undertaken.
At that time, the Ozone Layer was taken for granted. It had existed throughout the history of mankind and it hadn’t occurred to anyone that things might change.
However, in 1970 scientists began to suggest that this vital protection from the sun’s radiation could be affected by the actions of mankind.
And very soon afterwards, they confirmed that we had been unwittingly damaging the Ozone Layer –and putting our whole environment at risk - for at least half-a-century, through the use of man-made chemicals known as ODS – Ozone Depleting Substances.

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