By weight, we’ve done more to transform the planet’s atmosphere with the production of carbon emissions than we’ve done to the planet’s surface through the engineering and production of everything that humans ever built still standing today. Think about that for a second. (1/x)
https://twitter.com/dwallacewells/status/1586014177675554821
When you hear about carbon in the atmosphere, most of what you hear is that it’s increasing. Sometimes, numbers are cited, typically measures of “parts per million” concentrations: we’re at about 420, up from 280 from before the industrial revolution. 350 is considered “safe.”
When I was born, on August 5, 1982, carbon was at 340 ppm—just below that “safe” level. It is now at 420, and increasing by about 2 parts per million each year.
But another number is one trillion tons—that’s about as much carbon that’s been added to the atmosphere through human activity over the last several hundred years. The total "anthropogenic mass" of the global built environment has been estimated just below that level.
Everything we have constructed on the planet, as a species, over the last hundred thousand years—we’ve done more than that to the atmosphere in just three centuries of adding carbon. And all that carbon is doing one thing: heating the planet. That weight is a weighted blanket.
In fact, because the planet has absorbed about half of the carbon humanity has emitted, leaving half to accumulate in the atmosphere, we've produced in total more than two trillion tons of carbon in industrial history—twice the total mass of the entire built environment today.
The term “greenhouse gas” implies a flimsy pane; “parts per million” suggests a dissipating trace.
But while carbon concentrations will fall if emissions cease, they will fall very slowly, returning to preindustrial levels ultimately only after many millennia—in the meantime a a quasi-permanent atmospheric monument to the fossil-fuel age.
Indeed, much longer lasting, as a monument, than anything we've ever built on the earth's surface. (x/x)
• • •
Missing some Tweet in this thread? You can try to
force a refresh
