Reflecting on how the Icelandic volcano brought much of life in Europe — especially economic life — to a near-standstill in Europe, badly inconvenienced travelers waxed philosophical:

“I think Europe weirdly needs this kind of occasion to be reminded that life is tougher,” Mr. Dreznin said.
That lesson appeared to have been widely absorbed, and not just by Europeans.
A manufacturing and sales team from 3M in Minneapolis split on how to get home from central England. “We are on Plan E right now,” said Frank Klink, a laboratory manager for the company. “We were thinking Plan F or G might actually involve a ship.”
Brent West, the American general manager of a company that makes parts for the gas industry, had packed only a shirt, underwear and a pair of socks for what he thought would be a lightning-quick one-day trip from his headquarters in England to Finland.
After eight trains, three ferries and a car ride over three days, he has a new appreciation for the interlocked pieces of his world. “It makes you wonder whether you need to look more closely at things like your food sources,” he said.

I thought of that just now when I read a Foreign Policy article on “the gravest natural resource crisis you’ve never heard of”: the rapid decline of the world’s supply of phosphorus. Excerpt:

Phosphorus is used extensively for a variety of key functions in all living things, including the construction of DNA and cell membranes. As it is relatively rare in the Earth’s crust, a lack of phosphorus is often the limiting factor in the growth of plants and algae. In humans, it plays an essential role in bone formation. Without a steady supply of this resource, global agricultural production will face a bottleneck, and humankind’s growing population will suffer a serious nutrition shortage.
The world’s reliance on phosphorus is an unappreciated aspect of the “Green Revolution,” a series of agricultural innovations that made it possible to feed the approximately 4.2 billion-person increase in the global population since 1950. This massive expansion of global agricultural production required a simultaneous increase in the supply of key resources, including water and nitrogen. Without an increase in phosphorus, however, crops would still have lacked the resources necessary to fuel a substantial increase in production, and the Green Revolution would not have gotten off the ground.

More:

Our supply of mined phosphorus is running out. Many mines used to meet this growing demand are degrading, as they are increasingly forced to access deeper layers and extract a lower quality of phosphate-bearing rock (phosphate is the chemical form in which nearly all phosphorus is found). Some initial analyses from scientists with the Global Phosphorus Research Initiative estimate that there will not be sufficient phosphorus supplies from mining to meet agricultural demand within 30 to 40 years. Although more research is clearly needed, this is not a comforting time scale.

Here is more on the science behind the phosphorus shortage. Phosphorus — who knew?