15 Questions
What is the main function of the ozone layer?
Filtering the sun's ultraviolet (UV) rays
What is the chemical composition of ozone?
Three oxygen atoms (O-O-O)
Who discovered ozone during experiments regarding electrical odor?
Christian Schonbein
What is the relationship between ozone and UV rays?
Ozone protects against harmful effects of UV rays
What did Sterry Hunt hypothesize about ozone?
Ozone was just modified oxygen
What is the primary reason for the depletion of the ozone layer?
Use and production of CFCs
What was the goal of the Montreal Protocol?
To significantly reduce the production and use of CFCs
Why do astronomers rely on satellites for accurate UV readings?
Because the ozone layer filters UV radiations
What is the standard for ground-level ozone concentration defined by the EPA?
0.08 parts per million (ppm)
What is the projected timeline for the ozone layer to return to pre-1980 levels?
By about 2065
Who proposed the role of ozone in absorbing UV light?
W. N. Hartley
What did the British Antarctic Survey team report in 1985?
A hole in the ozone layer over the Antarctic
What is the average global density of ozone measured in Dobson Units (DU)?
About 300 DU
What can destroy ozone in the presence of UV light?
CFCs
What has prompted global action, including the banning of CFCs?
Ozone depletion
Study Notes
The Ozone Layer: Importance, Measurement, and Depletion
- Ozone was recognized as a vital component of the atmosphere by the 1870s, and its role in absorbing UV light was proposed by W. N. Hartley.
- G. M. B. Dobson's invention of a spectrometer in the 1920s enabled precise measurement of atmospheric ozone, revealing day-to-day and seasonal fluctuations.
- Sherwood Rowland and Mario Molina's fluorocarbon-ozone theory in 1974 demonstrated that CFCs could destroy ozone, leading to the ban of CFCs in aerosol sprays by 1979 and their Nobel Prize in 1995.
- The British Antarctic Survey team reported a hole in the ozone layer over the Antarctic in 1985, which expanded each spring, raising concerns and prompting global action.
- The ozone layer is located in the stratosphere, approximately 10-30 miles from the Earth's surface.
- Ozone concentration in the stratosphere averages at 12 parts per million (ppm) and is measured in Dobson Units (DU), with a global average density of about 300 DU.
- Ozone distribution varies globally, with lower densities near the tropics and higher densities toward the poles, influenced by wind patterns and the Brewer-Dobson circulation.
- Ozone is created through chemical reactions between UV, nitrogen oxides, and volatile organic compounds, while it can be destroyed by CFCs, chlorine, and nitrogen dioxide in the presence of UV light.
- The ozone layer filters the sun's UV rays, protecting humans from health issues such as sunburn, skin cancer, and cataracts, and also impacts plant growth, ecosystem health, and crop yields.
- Ozone depletion has been observed, with a 3-6% decrease in concentrations after 1979 and the discovery of a hole in the ozone layer, raising concerns about its impact on life on Earth.
- The ozone layer is threatened by manufactured chemicals, industrial processes, and emissions, with CFCs posing a significant risk to its stability.
- Ozone depletion has prompted global action, including the banning of CFCs, and ongoing efforts to monitor and protect the ozone layer.
Test your knowledge about the ozone layer with this quiz covering its importance, historical measurements, causes of depletion, and global actions taken to protect it. Learn about the significance of the ozone layer, its measurement in Dobson Units, the impact of CFCs, and the ongoing efforts to safeguard this crucial part of the Earth's atmosphere.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
