Ozone depletion | Wikipedia audio article
Channel: wikipedia tts
Date: 2018-12-02

This is an audio version of the Wikipedia Article:
Ozone depletion


00:02:04 1 Ozone cycle overview
00:06:37 2 Observations on ozone layer depletion
00:10:12 2.1 Chemicals in the atmosphere
00:10:21 2.1.1 CFCs and related compounds in the atmosphere
00:12:29 2.2 Computer modeling
00:13:12 3 Ozone hole and its causes
00:16:44 3.1 Interest in ozone layer depletion
00:19:40 4 Consequences of ozone layer depletion
00:20:32 4.1 Increased UV
00:21:55 4.2 Biological effects
00:23:00 4.2.1 Basal and squamous cell carcinomas
00:23:54 4.2.2 Malignant melanoma
00:24:54 4.2.3 Cortical cataracts
00:25:43 4.2.4 Increased tropospheric ozone
00:26:19 4.2.5 Increased production of vitamin D
00:26:44 4.2.6 Effects on animals
00:27:36 4.2.7 Effects on crops
00:28:17 5 Public policy
00:36:35 5.1 ODS requirements in the marine industry
00:37:20 6 Prospects of ozone depletion
00:39:29 7 Research history
00:41:44 7.1 Rowland–Molina hypothesis
00:45:26 7.2 Antarctic ozone hole
00:49:40 7.3 Arctic ozone hole
00:51:54 7.4 Tibet ozone hole
00:52:30 7.5 Potential depletion by storm clouds
00:52:52 8 Ozone depletion and global warming
00:56:17 9 Misconceptions
00:56:27 9.1 CFC weight
00:57:02 9.2 Percentage of man-made chlorine
00:59:03 9.3 First observation
01:00:16 9.4 Location of hole
01:00:52 10 World Ozone Day
01:01:18 11 See also



Listening is a more natural way of learning, when compared to reading. Written language only began at around 3200 BC, but spoken language has existed long ago.

Learning by listening is a great way to:
- increases imagination and understanding
- improves your listening skills
- improves your own spoken accent
- learn while on the move
- reduce eye strain

Now learn the vast amount of general knowledge available on Wikipedia through audio (audio article). You could even learn subconsciously by playing the audio while you are sleeping! If you are planning to listen a lot, you could try using a bone conduction headphone, or a standard speaker instead of an earphone.

You can find other Wikipedia audio articles too at:
https://www.youtube.com/channel/UCuKfABj2eGyjH3ntPxp4YeQ

You can upload your own Wikipedia articles through:
https://github.com/nodef/wikipedia-tts



"The only true wisdom is in knowing you know nothing."
- Socrates



SUMMARY
=======
Ozone depletion describes two related events observed since the late 1970s: a steady lowering of about four percent in the total amount of ozone in Earth's atmosphere (the ozone layer), and a much larger springtime decrease in stratospheric ozone around Earth's polar regions. The latter phenomenon is referred to as the ozone hole. There are also springtime polar tropospheric ozone depletion events in addition to these stratospheric events.
The main cause of ozone depletion and the ozone hole is manufactured chemicals, especially manufactured halocarbon refrigerants, solvents, propellants and foam-blowing agents (chlorofluorocarbons (CFCs), HCFCs, halons), referred to as ozone-depleting substances (ODS). These compounds are transported into the stratosphere by the winds after being emitted from the surface. Once in the stratosphere, they release halogen atoms through photodissociation, which catalyze the breakdown of ozone (O3) into oxygen (O2). Both types of ozone depletion were observed to increase as emissions of halocarbons increased.
Ozone depletion and the ozone hole have generated worldwide concern over increased cancer risks and other negative effects. The ozone layer prevents most harmful UVB wavelengths of ultraviolet light (UV light) from passing through the Earth's atmosphere. These wavelengths cause skin cancer, sunburn and cataracts, which were projected to increase dramatically as a result of thinning ozone, as well as harming plants and animals. These concerns led to the adoption of the Montreal Protocol in 1987, which bans the production of CFCs, halons and other ozone-depleting chemicals.
The ban came into effect in 1989. Ozone levels stabilized by the mid-1990s and began to recover in the 2000s. Recovery is projected to continue over the next century, and the ozone hole is expected to reach pre-1980 levels by around 2075. The Montreal Protocol is considered the most successful international environmental agreement to date.