Dan Egan, author of The Death and Life of the Great Lakes (which I read last November while staring out at one of them), explains in yesterday's New York Times how climate change will cause problems here in Chicago:
[T]he same waters that gave life to the city threaten it today, because Chicago is built on a shaky prospect — the idea that the swamp that was drained will stay tamed and that Lake Michigan’s shoreline will remain in essentially the same place it’s been for the past 300 years.
Lake Michigan’s water level has historically risen or fallen by just a matter of inches over the course of a year, swelling in summer following the spring snowmelt and falling off in winter. Bigger oscillations, a few feet up or down from the average, also took place in slow, almost rhythmic cycles unfolding over the course of decades.
In 2013, Lake Michigan plunged to a low not seen since record-keeping began in the mid-1800s, wreaking havoc across the Midwest. Marina docks became useless catwalks. Freighter captains couldn’t fully load their ships. And fears grew that the lake would drop so low it would no longer be able to feed the Chicago River, the defining waterway that snakes through the heart of the city.
That fear was short-lived. Just a year later, in 2014, the lake started climbing at a stunning rate, ultimately setting a record summertime high in 2020 before drought took hold and water levels started plunging again.
Egan explains in detail what that means for us, culminating in the harrowing near-disaster of 17 May 2020, when record rains combined with a record-high lake to make draining downtown Chicago almost impossible.
I should note that, after falling for 11 consecutive months, the lake has started to rise again (blue line), and we haven't even gotten down to our long-term average (green line):
I've said for decades that Chicago will fare better than most places, but that doesn't mean we'll have it easy. Nowhere will.