In her wondrous “Timefulness: How Thinking Like a Geologist Can Help Save the World,” geologist Marcia Bjornerud educated me on the scaling of Earth’s 4.5 billion years of existence. I read it during a time of inner turmoil, a time of weighing desk work against activism, a period crushed by competing projects. Bjornerud pierced my intensity with passionate prose and jewels of knowledge. For example, check out the table extract above. I was fascinated by the “residence time” of water, that is, how long it stays in a given place. In the atmosphere, it’s only nine days (really? water typically zaps in and out of our air over only nine days?), in rivers it’s two to six months, in glaciers it’s way over 100,000 years.
And this: we’re not only altering our home planet through carbon emissions, the scale of our impacts is huge in more prosaic ways:
The coal-mining practice of “mountaintop removal”—a deceptively surgical term—moves volumes of rock that rival the largest natural disasters. … Worldwide, humans now move more rock and sediment, both intentionally through activities like mining, and unintentionally by accelerating erosion through agriculture and urbanization, than all of Earth’s rivers combined. It can no longer be assumed that geographic features reflect the work of geologic processes.