Ozone hole + layer

[marcquelle]

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Um what do we need to know about it. Cause all i know is about the polar vortex in antartica that stops its temperature mixing with the lower latitidude therefore not allowing for the easy diffusion of CFCs and HCFCs from the stratosphere into the thermosphere so the hole remains over it in the winter.

What else do we need to know. PLEASE PLEASE HELP

[ajay098]

im not sure wat u mean....i have not learn wat u wrote in the thread...all i was taught about ozone layer - learn how CFC effects it, assess methods that have replace CFCs, assess the evidence to show that CFC deplete ozone and instruments that measure the ozone layer. ( i thk that's it in simple terms)

[marcquelle]

Originally Posted by ajay098

im not sure wat u mean....i have not learn wat u wrote in the thread...all i was taught about ozone layer - learn how CFC effects it, assess methods that have replace CFCs, assess the evidence to show that CFC deplete ozone and instruments that measure the ozone layer. ( i thk that's it in simple terms)

i have never been taught that (except the effects of CFCs) so I'm Fucked O_o FML /wrists

[annabackwards]

Oh yeah, there was some project in Antartica in 1987, called the Airborne Antarctic Ozone Experiment.

Basically they monitored concentrations of chemicals in the air to monitor ozone and found that there was less ozone in the air in spring (decreased by 80%) whereas there was plenty in winter. They realised that this was because of CFCs - during spring there is UV light which photodissociates CFCs, producing a chlorine free radical which then floats up to the stratoshere and destroys the ozone layer.

Other than that, you need to know a total of 3 equations for CFCs

CF3Cl ---> Cl. + CF3. (UV catalyst)
Cl. + 03 --> ClO. + O2
ClO. + O. --> Cl. + O2

And so chlorine radical continuously breaks down the Ozone layer as shown above

[ajay098]

Also,

replacements - HFC and HFC (some points about them)

- both are replacing CFC in frigeration and air conditioning
- they have no cl - zero ozone depletion potential
- however not as effective as CFC
- both are flammable
- light breaks the CH bond which decompose in troposphere - supposed no harm

Instruments

·Ground based instruments used to monitor stratospheric ozone are UV spectrophotometers which measure the intensity of light received at a wavelength at which ozone absorbs and then at wavelengths either side of this which ozone does not absorb. A comparison of these intensities gives a measure of the total ozone in the atmosphere per unit area at that location.>>
> >
·Spectrophotometers on board satellites have been able to scan through the atmosphere measuring the ozone concentration as a function of altitude and geographical position.>>
> >
·Ozone levels are measure by satellite spectroscopically. The Total Ozone Mapping Spectrometer (TOMS) measures ‘the total ozone column ozone’, the total amount of ozone in a column of air from the Earth’s surface to the upper atmosphere. It measures both the incoming solar energy directly from the Sun and the backscattered ultraviolet radiation at six wavelengths. Some of the backscattered radiation has been absorbed by ozone. The TOMS instrument can then compare the backscattered radiation to the incoming radiation which has not been absorbed, at identical wavelengths, and determine the amount of ozone above the Earth’s surface. >>

excuse the smiles....dun noe y they are there...

[marcquelle]

Originally Posted by annabackwards

Oh yeah, there was some project in Antartica in 1987, called the Airborne Antarctic Ozone Experiment.

Basically they monitored concentrations of chemicals in the air to monitor ozone and found that there was less ozone in the air in spring (decreased by 30%) whereas there was plenty in winter. They realised that this was because of CFCs - during spring there is UV light which photodissociates CFCs, producing a chlorine free radical which then floats up to the stratoshere and destroys the ozone layer.

Other than that, you need to know a total of 3 equations for CFCs

CF3Cl ---> Cl. + CF3. (UV catalyst)
Cl. + 03 --> ClO. + O2
ClO. + O. --> Cl. + O2

And so chlorine radical continuously breaks down the Ozone layer as shown above

oh thanks

[annabackwards]

Originally Posted by marcquelle

oh thanks

Read what Ajay said too, you need to know that

But just note that before the used CFCs they used Halons which were even worse because they contained bromine, which destroys the Ozone at a faster rate than the chlorine in CFCs do.

Also, UV spectrophotometers are placed in helium balloons and released into the atmosphere so that direct readings can be taken ^^

[marcquelle]

Originally Posted by ajay098

also,

replacements - hfc and hfc (some points about them)

- both are replacing cfc in frigeration and air conditioning
- they have no cl - zero ozone depletion potential
- however not as effective as cfc
- both are flammable
- light breaks the ch bond which decompose in troposphere - supposed no harm

instruments

·ground based instruments used to monitor stratospheric ozone are uv spectrophotometers which measure the intensity of light received at a wavelength at which ozone absorbs and then at wavelengths either side of this which ozone does not absorb. A comparison of these intensities gives a measure of the total ozone in the atmosphere per unit area at that location.>>
> >
·spectrophotometers on board satellites have been able to scan through the atmosphere measuring the ozone concentration as a function of altitude and geographical position.>>
> >
·ozone levels are measure by satellite spectroscopically. The total ozone mapping spectrometer (toms) measures ‘the total ozone column ozone’, the total amount of ozone in a column of air from the earth’s surface to the upper atmosphere. It measures both the incoming solar energy directly from the sun and the backscattered ultraviolet radiation at six wavelengths. Some of the backscattered radiation has been absorbed by ozone. The toms instrument can then compare the backscattered radiation to the incoming radiation which has not been absorbed, at identical wavelengths, and determine the amount of ozone above the earth’s surface. >>

excuse the smiles....dun noe y they are there...

thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you thank you :d

[annabackwards]

^
Perhaps you should download some chemical monitoring and management off the BoS resources section

[marcquelle]

i know all the other stuff about water now, its just the atmosphere stuff is so confusing cause my textbook goes on about all this stuff and i have no idea, and i need things put into lae terms to understand it then i can read it and make sense of it (if that makes sense). But thanks for all you help

[annabackwards]

Originally Posted by marcquelle

i know all the other stuff about water now, its just the atmosphere stuff is so confusing cause my textbook goes on about all this stuff and i have no idea, and i need things put into lae terms to understand it then i can read it and make sense of it (if that makes sense). But thanks for all you help

Ah, fair enough. I don't even remember where i put my textbook XD

Good luck for tomorrow!

[marcquelle]

OH I'm going to need more than luck, i'm going to need the chemistry fairies come and do my test for me (just like the ones who cobble shoes at night) . One can only life with optimisum