You can similarly make diamond from atmospheric CO2 (very energy intensive however), which is a pretty stable material.
Hydrogen itself is very difficult to store and transport, but it's critical for things like making steel without fossil fuels and for ammonia fertilizer production. Currently it's all made via steam reforming of natural gas at the industrial point of use, so if you can make methane from air and water, you don't have to rebuild all that infrastructure.
It's implausible to expect much effect on reducing global warming, however, at best we'll be able to stabilize atmospheric CO2 (assuming we don't run into major natural positive feedbacks from permafrost melt and shallow marine sediment outgassing, anyway). Any such speculation is also predicated on elimination of fossil fuels from the energy mix, which doesn't seem to be likely for decades at best.
https://arpa-e.energy.gov/technologies/projects/carbon-fiber...
You can similarly make diamond from atmospheric CO2 (very energy intensive however), which is a pretty stable material.
Hydrogen itself is very difficult to store and transport, but it's critical for things like making steel without fossil fuels and for ammonia fertilizer production. Currently it's all made via steam reforming of natural gas at the industrial point of use, so if you can make methane from air and water, you don't have to rebuild all that infrastructure.
It's implausible to expect much effect on reducing global warming, however, at best we'll be able to stabilize atmospheric CO2 (assuming we don't run into major natural positive feedbacks from permafrost melt and shallow marine sediment outgassing, anyway). Any such speculation is also predicated on elimination of fossil fuels from the energy mix, which doesn't seem to be likely for decades at best.