Environmental impact of concrete
After water, concrete is the most widely used substance on Earth
If the cement industry were a country, it would be the third largest carbon dioxide emitter in the world, after Chine and the US.
By one calculation, we may have already passed the point where concrete outweighs the combined carbon mass of every tree, bush and shrub on the planet. Our build environment is, in these terms, outgrowing the natural one. Unlike the natural world, however, it does not actually grow. Instead, its chief quality is to harden and then degrade, extremely slowly.
