I learned something novel about how the ice age happened from this Freakishly Strong Base post by Morgan Housel:

The prevailing idea before [Wladimir] Köppen was that ice ages occur when the earth’s tilt supercharges the wrath of cold winters. Köppen showed that wasn’t the case. Instead, moderately cool summers are the culprit.

It begins when a summer never gets warm enough to melt the previous winter’s snow. The leftover ice base makes it easier for snow to accumulate the following winter, which increases the odds of snow sticking around in the following summer, which attracts even more accumulation the following winter. Perpetual snow reflects more of the sun’s rays, which exacerbates cooling, which brings more snowfall, and on and on.

You start with a thin layer of snow left over from a cool summer that no one pays much attention to, and after a few tens of thousands of years the entire earth is covered in miles-thick ice.

Fascinating! The blog goes on to apply the idea to that strong base, accumulating a bit at a time, to investing and business. The power of compounding seems appropriate to share on the day Jeff Bezos announced his retirement.

I’ll leave you with one of my favorite quotes from Charlie Munger, which is also how the article ends:

The iceberg photo is one I took near Svalbard in 2011.