How much of an impact do Fourth of July fireworks in the U.S. have on pollution and global warming? originally appeared on Quora - the knowledge sharing network where compelling questions are answered by people with unique insights.
Answer by Kynan Eng, who specializes in tech startups, research, neuromorphic engineering, and Big Mobile data, on Quora:
The July 4th fireworks probably contribute to less than 0.01% of global anthropogenic atmospheric pollution on that one day. But they do release a lot of junk in local areas.
According to an article from the US Evironmental Protection Authority, fireworks on the 4th of July cause a temporary spike of airborne particulates of around 42% in the USA. But what about global effects in terms of release of greenhouse gases? A brief search reveals the following data:
- In 2013, fireworks sales reached about $990M in the USA. About two-thirds of this was to consumers; the rest was for commercial fireworks.
- A typical medium-sized firework is a "cake" with about 200g of gunpowder.
- A typical 200g cake costs about $17.
From these numbers, we can work out that the money spent on fireworks in the USA in one year corresponds to around 52.8 million medium "cakes", or 10.59 millon kg of gunpowder. We'll ignore volume discounts for this calculation, and assume the worst case that all fireworks are set off on the 4th of July.
Gunpowder has an energy density of approximately 3 MJ/kg. So we are dealing with approximately 31.7 million MJ of energy in total. This is equivalent to burning around:
- Gasoline: 683,000 kg, or 950,000 L or 8000 barrels (world consumption 93 million barrels/day)
- Coal: 1056 t (world consumption ~8 Mt/day)
Each of these figures correspond to approximately 0.01% of global usage. Gunpowder is composed of nitrates, charcoal and sulfur, i.e. it is relatively dirty and pollutes more like coal than gasoline.
So in summary: the July 4th fireworks release a lot of junk temporarily into the atmosphere around where they are discharged, but have little effect on global warming. I am guessing that the Chinese New Year fireworks would have a similar effect.