1. Limitations of Tree Planting for CO2 Sequestration
Trees provide only temporary storage, release CO2 upon death or fire, and cannot scale globally.
roflmaostc: "you cannot plant enough trees around the globe to offset our CO2 emissions. Also, a forest only absorbs CO2 while alive. Once it dies, it emits CO2 too."
adregan: "Trees are short term storage, and sometimes the storage is a lot shorter than popular imagination purports."
2. Massive Scale and Physics/Economics Constraints on DAC
Direct air capture requires enormous volumes, energy, and logistics, making it impractical at global levels.
yodon: "you're talking not about making a pile of stuff but about making a mountain range that's a mile high and hundreds of miles long."
sfn42: "you have to suck the entire atmosphere into these carbon capture facilities."
3. Need for Permanent Storage Solutions
Captured CO2 must be locked away long-term via methods like biochar, mineralization, or wood products.
xnx: "Biochar seems like a good option."
Yizahi: "Even if we do magic and emit nothing, we still need to remove CO2 from the atmosphere or it will cook us over time, just longer."
mnky9800n: "you can inject it into peridotites and let it mineralize... store it there indefinitely."