Polution is a very big issue. It has changed climate and caused many species to go extinct or endangered. You may say that not all these animals matter to the human race, but the "Horse Shoe Crab's" blue blood is vital to surprisingly many medical treatments and polution is large impacts to the food chain concerning this ancient creature.
Another serious threat to the planets climate is multiple holes in the Ozone (O3) that are rapidly frying the planet, melting the ice caps causing the oceans to flood and destroying beach side residence. One more large threat to the human race caused by the depleeting Ozone layer is the sun's UV rays coming to earth and highly increasing the risk of skin cancer.
The gas O3 rarely occurs naturaly so the Ozone layer has little ways of being replenished. But although our technology hasn't exactly helped polution there is a under apreciated device that can produce Ozone very well. It's simply known as an "Ozone Generator". Ozone Generators produce Ozone quite well and they are available on market.
Ozone Generators are also surprisingly easy to make with a few house hold items, some high voltage wire and a 6,000 volt transformer (found in light up neon "OPEN" signs). I might post instructions for the D.I.Y. O3 generator another time.
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