As Utah’s 2022-23 legislative session approached, dozens of scientists called on lawmakers to prevent the “unprecedented danger” that would occur if the alarming rate of decline of the Great Salt Lake continued. Without action, they warned, the lake could (not would) dry up “in the next five years.”
Three months later, in the midst of the snowiest winter and spring on record, the lake’s surface has risen about three feet. With snowpacks at record levels, we’re likely to see several more feet of rises later this spring and beyond.
Did the report’s authors get it wrong? Not entirely. They cautioned that the lake could potentially disappear in as little as five years if there was not a significant increase in water flow, which fortunately we have now received.
But the report’s writers did not strongly emphasize these nuances, and some journalists and social media users who shared the report may have overlooked them while emphasizing the alarming message. Similarly, in the past, some people have cited a few reports that suggested a possible future of “global cooling” while ignoring the overwhelming evidence that human activities are causing global temperatures to rise. In the same way, skeptics could soon cite this report’s predictions about the Great Salt Lake drying up.
They might look out over a lake in 2027 that has not dried up and say, ‘I remember when the scientists said this lake was about to disappear.’
That’s unfortunate, because the lake may still be in trouble.
To understand that peril, we must understand the natural climate cycles that drive the ups and downs of the Great Salt Lake. These cycles are connected to chaotic jet streams and prominent oscillations in the world’s oceans — shifts in temperature resulting in changes to ocean evaporation, pressure and wind (and the moisture it carries) toward the Mountain West. These shifts impact precipitation, snowpack, river flow and groundwater and can be seen in tree-ring reconstructed records of climate conditions going back hundreds of years.
The moist peaks of this cycle tend to come every 8 to 16 years. Some are higher and some are lower, but the long-term trends can’t be seen in any one cycle of the oscillation — they’re much better viewed over many decades. In the past 50 years, for instance, the highs and lows appear to have diverged quite significantly from those seen in earlier data. This is why the amazingly wet winter and spring of 2022-23 weren’t really a surprise.
Warmer air holds more moisture, resulting in more precipitation in certain regions, such as ours, when the right underlying conditions are present, like when the natural oscillation is trending toward a wetter winter to begin with.
On the other hand, warmer air can cause surface moisture to evaporate before it seeps into the soil enough to become persistent groundwater, which slowly percolates toward the terminal lake. Warmer temperatures also enhance evaporation from the lake itself, particularly when the natural oscillation is already trending toward drought.
While the natural climate cycle may be affected by warming, it is distinct from the acute changes associated with climate change and increased water consumption. It existed before human-caused changes to our climate, and it will likely still exist even if we shed our dependence on fossil fuels.
This doesn’t mean we shouldn’t care about water consumption, as the natural climate cycle does amplify how we use water, which could result in a dry lakebed at some point. As a state, we need to address the overuse of water in all sectors. But we also need to predict better and respond swiftly to the natural climate cycle, so that we can make increasingly accurate decisions regarding water trends and management.
This will better ensure a supply for our fundamental needs and help us predict, prepare for and even prevent droughts and floods.
That won’t happen if many more people in our state decide they can’t trust science. To that end, it’s most responsible for noting that while it is possible that the total evaporation of the Great Salt Lake is nigh, the natural wet-dry cycle that is currently occurring will have a tremendous influence over when and whether that outcome arrives.
Simon Wang is a professor of climate science at Utah State University. He has been the author or co-author of hundreds of studies on weather extremes, climate variability and climate forecasting.