Chicago, famous around the globe for exotic outdoor violence, is undergoing a spike in bodies being discovered in the city's waters.  According to CWB Chicago:

Local media outlets have been making a bit of hay over the fact that authorities have recovered four bodies from the Chicago River and Lake Michigan over the past week

But rather than sound the alarm at a wave of aquatic criminality, the author wisely notes an article published in the Chicago Tribune in 1993.

[W]hat causes the annual spike in waterway bodies?

When a person drowns, the lungs — which are normally full of air — compress as the body goes to the bottom, a spokesman for the Cook County Medical Examiner said. As the tissue begins to decompose, it creates gases which fill those cavities, and the body comes to the surface.

When the water is extremely cold, it slows and nearly stops that process. A body may remain at the bottom for months in the winter, but it surfaces in three to six days when the water is warmer.

Read Recktenwald's piece for the full explanation.

As the swallows to Capistrano and the cherry blossoms to Washington, D.C., natural cycles bring seasonal phenomena every spring.  Alongside those wonders, Chicago has its corpse season, hardly something to celebrate, yet consistent with the city's brand.

Hat tip: Peter von Buol.

Photo credit: Steve Shook, CC BY 2.0 license.