Sustainable AI

Chapter 10. Toward Sustainable AI

For much of our history, agriculture was constrained by the natural nitrogen cycle. Usable nitrogen was scarce, and farmers relied on manure, compost, and legumes to restore soil fertility.¹ These limits kept the yields modest, and food production was tightly coupled to ecological rhythms.

With the invention of the Haber-Bosch process in the early 20th century, however, scientists unlocked the ability to produce synthetic fertilizer at industrial scale by synthesizing ammonia from atmospheric nitrogen. This had a transformative effect on food production and agriculture as crop yields soared, famine declined, and the Green Revolution brought this power to fields across the globe.²

But the efficiency gains that synthetic nitrogen unlocked came with unintended consequences. Figure 10-1 shows the historical trend of nitrous oxide (N₂O) in the atmosphere. Like other GHGs, N₂O levels rose sharply with industrialization beginning in the 19th century. What sets N₂O apart, however, is that the vast majority of its increase is from agriculture—primarily as a byproduct of the Haber-Bosch process, which underpins modern intensive industrial farming.³

Figure 10-1. Historical trend of nitrous oxide levels measured in parts per billion (PBB). (Source: Two Degrees Institute.)

Rather than reducing environmental pressures, the rapid scaling of agriculture introduced ...