You might well be forgetting the analyses showing a vast increase in elemental atmospheric hydrogen from the introduction of a hydrogen infrastructure. Even conservative estimates put it at a loss of some 10 to 15% of total production escaping into the atmosphere.smkettner said:I think I remember learning at one point that Earth's gravity is insufficient to retain hydrogen or helium.
They rise up and and basically leave for outer space. Trace amounts must remain diffused for other reasons.
Pulling hydrogen from the air is a lost cause IMO.
In fact, the percentage losses possible are enough to destabilise the current bio-active soil-based sinks for elemental hydrogen that can fix it and which stabilise the current 500ppb.
It is not inconceivable that 'H2' as a 'solution' to reducing CO2 could have the perverse effect of destroying the planet's atmosphere. The risk is very low, but it is a possibility. There is no risk that CO2 could 'destroy' the atmosphere because it is a naturally occurring gas, but free hydrogen could destroy the ozone layer that make decades of CFCs look like an ant's fart. It'd be real great to end up with a 'solution' to the high levels of chemically inactive anthropogenic CO2 emissions that ends up destroying the ozone layer and all surface life on earth with anthropogenic atmospheric elemental hydrogen. Nice result!