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Comment by TheAdamAndChe | Hacker News Reader

Why? I thought Carbon Dioxide was one of the most innocuous oxides released by engines, both in environmental and health effects.

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That's true. As a pollutant, carbon dioxide is almost entirely innocuous, except for its behavior as a greenhouse gas. In that role, carbon dioxide is the most significant driver of global warming: https://en.wikipedia.org/wiki/Greenhouse_gas#Natural_and_ant...

Methane is worse.

A methane molecule is 72 times worse than a CO2 molecule in terms of "global warming potential" over a 20 year time scale and around 7 times worse over a 500 year time scale). However, we put a lot more CO2 into the atmosphere than we do methane. https://en.wikipedia.org/wiki/Greenhouse_gas#Global_warming_...

Doesn't that indicate methane is the low hanging fruit? I guess that assumes it's the same cost to prevent / recapture 1 molecule of methane vs. CO2... But if the next 20 yrs are the most crucial, methane sounds like a great target.

seems likely; after that, technology will hopefully have stabilized our energy sources

Gram for gram or tonne for tonne, most other stuff is much worse. But mile for mile and kWh for kWh, the relative quantity of CO2 more than makes up for its relative harmlessness.

(Except maybe in dirty ships where there is much more of the nasty stuff per tonne of CO2 than in the exhaust gases of any other mode of transportation - they are basically using the skies over international waters to dispose of refinery waste that would be impossible to legally burn anywhere else)

The total volume of emitted carbon dioxide, of which land vehicles are a major contributor, is a significant factor in global climate change. An insufficiently specific headline that can be read to imply otherwise is thus misleading.

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