[LarryMullins]

While as far as I can tell the Great Salt Lake's level is presently severely low due to human actions, reconstructions of the historic level of the lake from tree ring analysis shows that the lake's natural level fluctuates substantially even when humans aren't doing anything to it. So even if water diversions stopped, the GSL area would still have a long-term problem on their hands. The toxic lake bed will get exposed one way or the other, if not through the actions of men then through natural fluctuations. Given that the lakebed is already contaminated and there's no way to fix that, the best solution is to live someplace else.

> For example, the driest (wettest) year on record, 1581 (1464) occurred many centuries ago and was substantially larger in magnitude than the historical record. At lower frequencies, the GSL lake-level reconstruction revealed large, multi-year reductions in lake levels from 1580–1600, in the 1630s, and from 1700–1710 that in each case were at least as severe as the known lake-level minima during the drought of the 1930s and 2000–2001 (Figure 3).

https://www.srs.fs.usda.gov/pubs/46447

Incidentally, the "many centuries ago" framing is revealing of a general attitude I've noticed from Americans, particularly Americans living in the western half of the country. They think "several centuries" is essentially an eternity because in their region, several centuries ago is before recorded history. And in a sense, for an individual human planning their life, several centuries may as well be an eternity. But for city planning, an environmental problem that's likely to be disastrous for the city every few hundred years should be considered a severe threat. That sort of circumstance makes for a city that won't survive the test of time.

Another example of this sort of short-term thinking is water levels in California. According to tree stump analysis, California has been unusually wet since America acquired the land; this luck will not last. California had, and will have again, droughts which are far more severe than any Californian drought in living memory. Californian communities should be planning to deal with such severe droughts, but many Californians seem to prefer believing that they can somehow stabilize the Californian climate to always be the way it was when they were kids.

[ilammy]

> Incidentally, the "many centuries ago" framing is revealing of a general attitude I've noticed from Americans

They don’t say “in Europe 100 miles is a long way, in America 100 years is a long time” for nothing.

100 years ago WW1 just finished. 200 years ago saw a peak of slave imports into US. 300 years ago thirteen colonies just finished forming. 400 years ago colonization just started. 500 years ago Columbus’ expeditions were still news.

Not to say that nothing happened in Europe in the meantime lol, but this sets a perspective quite well. “100 years ago” is effectively “eternity” for an individual human. Only societies can retain memories at that scale.

[ploika]

Surely you don't consider your grandparents' childhoods to be "eternity" ago.

[arcticfox]

I feel almost maybe 80% as removed from WWI-era society as I do from Roman society, tbh. It's almost equally hard to imagine living in either era. Post-WWII (my parents' childhood's) starts to feel more connected. I imagine this is wildly different for individuals. For me, 100 years ago does feel about "an eternity" ago.

[groestl]

> I imagine this is wildly different for individuals.

It's definitely different if you happen to live in an old European city like Vienna (like I do). There's castles, buildings and places named after people and events from that era everywhere. Everytime you get tap water you're reminded (Wiener Hochquellenwasserleitung). It's not hard to imagine living in the middle ages even, since there's lots of artefacts from that age too.

[andrewflnr]

There's a lot riding on the word "effectively", but in terms of how well I can imagine it or empathize with it, my grandparents' childhood is not far off any other time in history. The signal is mostly already gone.

[LarryMullins]

In many families, grandparents and particularly great-grandparents are 'pre-history'. I could tell you maybe about a dozen facts about the lives of two of my eight great grandparents, but that's it. What can I say about the childhoods of my grandparents if I hardly even know who their parents were?

[nerdponx]

All of this is valid, but that doesn't mean humans aren't making it worse than it needs to be. "It fluctuates anyway" is a common talking point for those who want to deny the effect of human activity.

[LarryMullins]

As I said: the Great Salt Lake's level is presently severely low due to human actions.

Long-term thinking is possible, and two example that comes to mind are Tsunami Stones in Japan and Hunger Stones in Europe. After disastrous Tsunamis, people in Japan would sometimes inscribe rocks up on hills, warning people not to live near the water lower than the rock. And during severe droughts in Europe, large stones exposed in dry rivers would sometimes be inscribed with warning about famine; "If you see me, cry"

Some of those stones are several hundred years old. America, particularly the western half, is substantially younger than many of these warning stones; the cultures inhabiting these regions today simply don't have much experience dealing with all the scenarios the land has to offer.

[labster]

This is the problem with science communication today. We can either be nuanced and the message can be taken whatever way a person wants to hear it, or we can be direct and people accuse you of ignoring nuance.

As a first order approximation, the lakes are drying from diversions. At second order, its diversions, climatic variability, and AGW. In reality: what about the feedback from aquifer depletion, does evapotranspiration from crops offset this from increased rainfall, and to what degree compared to native biota? Natural systems have irreducible complexity that no one wants to hear about.

[dmqctx]

Can you phrase it another way beginning at "what about the feedback". I'm curious about your comment, especially your point on evapotranspiration.

[scythe]

> The toxic lake bed will get exposed one way or the other, if not through the actions of men then through natural fluctuations. Given that the lakebed is already contaminated and there's no way to fix that, the best solution is to live someplace else.

> https://www.srs.fs.usda.gov/pubs/46447

That's not what Figure 3 says. The low point on the graph shows a lake level decline of about 120 centimeters (in 1581), but the average depth of the lake is 490 centimeters (Wikipedia). So the natural drying of the lakebed does not seem to be expected on a timeline of centuries.

[LarryMullins]

The chart shows year-to-year change, not lake level. It shows many periods in which the lake level drops year after year.

In any case, even temporary drops of a meter or less will expose some lakebed and contaminate the entire area. And that contamination sticks around. The area doesn't get much rain to wash it away, so the region will be progressively poisoned as time goes on. Short of large-scale geo-engineering projects, the SLC area seems doomed. Not a good place to set root and raise a family.

[scythe]

>The chart shows year-to-year change, not lake level.

Did you read the caption?

>Figure 3. Reconstructed Great Salt Lake water year level

The y-axis says "elevation change", which may be confusing, but it most likely means the difference from baseline. If the authors had uncovered evidence that the basin were completely dry, they would say that. It would be an interesting discovery: scientists want to highlight the interesting things they learned.

>The area doesn't get much rain to wash it away

Salt Lake City gets 95 days of precipitation per year, though the total is only 15 inches.

>Short of large-scale geo-engineering projects, the SLC area seems doomed. Not a good place to set root and raise a family.

This is completely unjustified by the evidence you've presented. If an area is definitely at imminent risk of catastrophe then scientists who study the region will be clear about that. See, for example, the Cascadia subduction zone, South Florida, the Salton Sea, and so forth.