Studies have confirmed that the popular thermal pools in the Yellowstone National park have undergone rapid changes in coloration over the last century or so which is mainly contributed by tourists. The park came into existence because of these hot springs in the first place so it can be said that they are the main center of attraction for tourists and therefore have been left at their mercy as well.
Yellowstone is one of the largest parks maintained by the U.S. National Park Service. It stretches across the three states of Wyoming, Idaho and Montana. The park was also America’s first and is under government protection since its inception way back in the last quarter of the 19th century.