Olivine Weathering Can Reverse Global Warming in Our Lifetime | Hacker News Reader

Olivine Weathering Can Reverse Global Warming in Our Lifetime

worksinprogress.co

44 pointsbarry-cotter9 comments

Un-burning all the fossil fuels we’ve burned obviously requires a level of industrial infrastructure on par with what it took to get to this point in the first place. The olivine method seems to be the most effective from the standpoint of thermodynamics and technological complexity, but one wonders what the side effects of dumping trillions of tons of olivine dust into the ocean in a relatively short period of time would be.

> one wonders what the side effects of dumping trillions of tons of olivine dust into the ocean in a relatively short period of time would be.

This is something that can be studied as marine layers already contain many examples of both slow and rapid depositation.

One example of grand scale carbonate deposits are the Bunda cliffs - 210 kilometres in length, 120 metres in height, some 20-30 km in width (the material of the cliff face extends inland).

https://en.wikipedia.org/wiki/Bunda_Cliffs

Silica dust particles of 10 microns are dangerous to breath. So there is a limit on how small the rocks can be crushed before beaches become a heath hazard.

The final proposal didn't involve beaches: it would spread the silt across the floor of the Java Sea. The calculation I kept waiting for, but never saw, was how many square miles of ocean floor this would take up, and what the damage would be to sea life (plus fishing, etc, industries) in the region.

(That's a valid point, however, about the expected hazards to the people running the milling machines. Maybe there are good ways to mitigate that? Maybe wet milling minimizes the problem? The author doesn't say.)

Silt can be incredibly destructive. Before hydraulic (gold) mining in the Sierras, the Sacramento river was navigable all the way to.... um, Sacramento, and the waters of San Francisco Bay were crystal clear, and carpeted with oysters. Silt washed down 150-ish years ago is still gunking up the entire ecosystem.

This is an intriguing idea, and global warming is a planetary emergency - so some degree of localized destruction may be a reasonable trade-off - but the author gets poor marks from me for leaving obvious negative externalities out of the article.

I was thinking of the Indonesians. If the silt washes onto beaches it could turn the coastline toxic during dry weather and, as you mentioned, the workers. And as you point out, if it turns bad it is going to be very long time to resolve.

The solution would be to keep thr particle size larger, at lower efficiency.

Pro Tip: Send the bill to the fossil fuel industry.

Those costs seem very low per tonne of co2. Even if it were more expensive, however, it would be worth doing as the alternative is so, so much greater.

Isn’t that what Minmus is made of?

Minmus is canonically made of mint ice cream, I believe

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