Nitrous Oxide is otherwise known as Laughing Gas. Ozone is actually highly toxic to human beings. To be avoided like the Plague.
Interesting developments at SpaceX.
SpaceX'''s Starship rocket lands but then explodes - BBC News
Third explosion in a row for Starship. They call it success? 😱
I think the Chief Engineer's job is on the line. Even my childhood rockets had a better success rate.
Don't ask what I used as propellant. Trade secret. 😀
Interesting developments at SpaceX.
SpaceX'''s Starship rocket lands but then explodes - BBC News
Third explosion in a row for Starship. They call it success? 😱
I think the Chief Engineer's job is on the line. Even my childhood rockets had a better success rate.
Don't ask what I used as propellant. Trade secret. 😀
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Not as bad,y as we have the last 50 yrs - changes in dress notwithstanding.
The ozone layer that opened up over Antarctica was caused by a loss of 40 billion tones off the stuff directly above it. Big numbers. UV is highly energetic and there was no complex life on the land prior to about 500 million years ago. So the ozone layer is quite a new feature. I’ve read the same things about the surface of Mars with is bathed in the stuff. UV kills comp,ex cellular life because it damages molecules or breaks them.
The ozone layer that opened up over Antarctica was caused by a loss of 40 billion tones off the stuff directly above it. Big numbers. UV is highly energetic and there was no complex life on the land prior to about 500 million years ago. So the ozone layer is quite a new feature. I’ve read the same things about the surface of Mars with is bathed in the stuff. UV kills comp,ex cellular life because it damages molecules or breaks them.
I did say that the ozone depletion mechanism involving nitrogen oxides happens during "strong solar storms".
Intense bombardment occurs when huge solar flares just happen to direct streams of high energy protons straight towards planet Earth.
Events like this happen infrequently, but what is significant is that such events produce an immediate change in the Earth's atmosphere.
The ozone in the Northern Hemisphere is reduced by less than 1% by a single one of these events, but the important point is that the Sun has the ability to produce sudden changes in the Earth's atmosphere.
@ Bonsai, Sure, if we bombard living cells to oblivion we can construct any outcome we choose. But where is the empirical evidence? All I see is purely anecdotal or data that tracks or confirms it's changing concentration. That's it. The natural undisturbed concentration is negligible, a single molecule per 3million. The layer itself is not much more, 10ppm. If that's sufficient to block uv from killing us, than we shouldn't be even going outside, a slight anomaly and you're dead!
Although ozone makes up only 0.00006 percent of the atmosphere, the total mass of ozone in the atmosphere is about 3 billion metric tons.
The above graph shows how effective the ozone layer is in protecting us against ultraviolet radiation.
We are totally screened against the most energetic UVc radiation and most of the UVb radiation, but ozone only screens us from about half of the UVa radiation.
It is the UVb and UVa radiation which cause sunburn and can lead to skin cancer and eye damage.
The above graph shows how effective the ozone layer is in protecting us against ultraviolet radiation.
We are totally screened against the most energetic UVc radiation and most of the UVb radiation, but ozone only screens us from about half of the UVa radiation.
It is the UVb and UVa radiation which cause sunburn and can lead to skin cancer and eye damage.
My post #5602 is absolute nonsense. Apologies.
The mass of the ozone lost over the hole in Antarctica is 40 million tons. I was out by 10^3
🙁
The mass of the ozone lost over the hole in Antarctica is 40 million tons. I was out by 10^3
🙁
I appreciate that but it still gives no perspective. How much uv is the Earth bombarded with overall? How much of the 'less' energetic uv is there? If there was no "most energetic" uvc, uvb, and uva at all and we completely destroyed the ozone layer, would we still be in trouble?
You appear to misunderstand my earlier statement, Pete.
The higher the frequency (the shorter the wavelength) of the UV, the more energetic it is.
Hence UVc is more energetic than UVb, which is more energetic than UVa.
The radiation intensity of the Sun is greatest in the visible band of frequencies.
Only around 7% of the total radiation from the Sun is ultraviolet radiation.
The attachment shows the variation of radiation intensity with frequency.
Attachments
So do we have examples of the direct effect of a full blown blast of uv from the Sun? Antarctica is one place a hole appears every year. Is there evidence of it at ground level? Are there other places where a hole has been detected?
Not completely, because the oxygen produced by photosynthesis forms a filter in the outer reaches of our atmosphere that absorbs the most energetic and harmful UV radiation - the high frequency UVc radiation.
In the process, the oxygen molecules split up and recombine to form ozone.
The ozone layer in the stratosphere absorbs UV radiation of lower frequencies than the oxygen in the upper atmosphere, but a part of the UV radiation in the UVb band still reaches ground level.
The less energetic radiation in the UVa band is not absorbed by ozone and reaches ground level without much attenuation on a cloudless day. Thankfully, the UVa radiation in sunlight is generally less harmful than UVb radiation.
Could we introduce a limit of one question at a time? I'll be here all night googling for the answers that you could google for yourself! 😀
First question first:
An example of the direct effect of a full blown blast of energetic protons (not UV as you stated) from the Sun occurred between July 14 to 16, 2000, causing scientific and communications satellites to short-circuit.
This is known as the Bastille Day event. Bastille Day event - Wikipedia
Now please, no more questions till I've attempted to answer the other two! 😉
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The hole has been shrinking IIUC, and so is not as bad as it was say 25 years ago.
The problem with UV - even though it accounts for only 7% of total irradiation is that it rips molecules apart. So it you have no protection, organisms (think primitive bacteria etc) get killed off if they are less that 5-10cm below the surface of the ocean. On the land, they don't survive at all. Only after the ozone layer is fully formed 500 million yrs ago can life move onto the land en mass. Before that its a barren wasteland - no trees, plants, nothing. All life is in the sea.
Today, even with the Ozone layer, cells get seriously damaged with the UV that does get through. When I was in Asia, I met a guy from Australia who got skin cancer. The Japanese doc that diagnosed it sent him straight back to Oz because he said that's where they had the most knowledge on the subject. Anyway, he got fixed up and came back to work 6 months later (skin grafts, hole in the neck etc). Years of swimming and cycling in the Australian sun had resulted in cumulative skin cell damage from UV that had triggered the cancer.
There's a lot of research data on this stuff - so its pretty serious. No Ozone, no life on the land. Period.
The problem with UV - even though it accounts for only 7% of total irradiation is that it rips molecules apart. So it you have no protection, organisms (think primitive bacteria etc) get killed off if they are less that 5-10cm below the surface of the ocean. On the land, they don't survive at all. Only after the ozone layer is fully formed 500 million yrs ago can life move onto the land en mass. Before that its a barren wasteland - no trees, plants, nothing. All life is in the sea.
Today, even with the Ozone layer, cells get seriously damaged with the UV that does get through. When I was in Asia, I met a guy from Australia who got skin cancer. The Japanese doc that diagnosed it sent him straight back to Oz because he said that's where they had the most knowledge on the subject. Anyway, he got fixed up and came back to work 6 months later (skin grafts, hole in the neck etc). Years of swimming and cycling in the Australian sun had resulted in cumulative skin cell damage from UV that had triggered the cancer.
There's a lot of research data on this stuff - so its pretty serious. No Ozone, no life on the land. Period.
Third question third:
There are no other places, apart from the Antarctic, where an ozone hole has formed.
The ozone hole over the Antarctic, which appears in late winter and early spring, is unique because atmospheric and chemical conditions unique to this region increase the effectiveness of ozone destruction by reactive halogen gases.
There are no other places, apart from the Antarctic, where an ozone hole has formed.
The ozone hole over the Antarctic, which appears in late winter and early spring, is unique because atmospheric and chemical conditions unique to this region increase the effectiveness of ozone destruction by reactive halogen gases.
Yes indeed!
It was around 2.5 billion years ago that Earth underwent what scientists call the Great Oxidation Event, as ocean microbes evolved to produce oxygen via photosynthesis.
Great Oxidation Event - Wikipedia
Via photosynthesis, life began to form its own oxygen/ozone protection against the most harmful UV radiation from the Sun.
That's evolution for you, Pete! 😉
Okay. But how is it possible for 10ppm to block 99%? That's almost nothing. What is the mechanism which enables this? How does it take place scientifically? I've been googling this stuff and I don't know how you guys are able to quickly round up answers to these questions. All I end up finding is basic data. 🙄
"That's almost nothing": Patently it's sufficient - because it happens! 😎
"What is the mechanism?": During the "ozone-oxygen cycle" mentioned earlier by Bonsai, harmful ultraviolet radiation is continuously converted into heat.
"How does it take place scientifically?": Messages from Space - The Ozone Hole From Space: How does ozone absorb UV light?
I think you'll find it is 99% of the UVc that is filtered out - and I read that this is by the oxygen in the extreme upper atmosphere.
That still leaves the UVb and UVa to be filtered (or not) by the ozone, as I quantified earlier.
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