It may not be easy to turn back the hands of time to see the effect humans have, but thanks to some creative mathematical modelling geologists have been able to make an accurate picture of one particular case. Published this week in the journal Applied Optics, Vol. 54, Issue 4., the researchers' study shows exactly how Yellowstone National Park's famous thermal springs looked decades ago, before tourism polluted the otherwise pristine pools.
As a destination for ecotourism, Yellowstone's hot springs and it's water display at Old Faithful are quite the sight to be seen. But with the many onlookers, the landscape of Yellowstone National Park, and that of the springs themselves, has changed significantly.
"There are people at my university who are world experts in the biological side of what's going on in the pools" lead author of the study, and professor at Montana State University, Joseph Shaw says. "As a result of coins, trash, and rocks thrown into the pool over time, the vent has become partially blocked, leading to a lower temperature and altered color pattern."
The "wishing well" practice, so common amongst other spring-like bodies of water, is the prime suspect for the thermal spring's chameleon meniscus. Couple this with the popularity of tourist throwing other large debris into the pools, anything from large rocks to bottle caps, and what you have now is a cooler body of water. Before the introduction of these foreign bodies, Yellowstone's thermal springs maintained a homeostatic temperature at 180 degrees fahrenheit. Now, they run a bit cooler―40 degrees cooler, to be exact. And it's this drop in temperature recorded that correlates into the vivid yellows, greens, and oranges that are now present in the pools. But that's not where the springs found themselves on the color wheel decades ago.
Thanks to the study, which was a collaborative effort between researchers at Montana State University and Germany's Brandenburg University of Applied Science, we now can chromatically speaking, travel back in time―and what the data tells us is that it used to be a bit more blue. Using one-dimensional models and microbial mapping, the academic team was able to optically recreate how the pools appeared before the decades of accumulated trash. And what "came to the surface" were the thermal springs' beautiful blues.
But in spite of the significant findings the study revealed, the researchers insist that it was their inquisitive natures that led them to this conclusion. And more importantly, they believe that it is the modeling techniques that are what's important here. Because as they say, the springs are still beautiful, and they're still warm.
"We didn't start this project as experts on thermal pools. We started this project as experts on optical phenomena and imaging, and so we had a lot to learn," Shaw says. "What we were able to show is that you really don't have to get terribly complex; you can explain some very beautiful things with relatively simple models."