Why are hot springs hot? In this leg of Sophie’s Electric Road Trip, Sophie Shrand of @sciencewithsophie explores Hot Springs National Park in Arkansas. Hot springs are formed when rainwater heats up under the surface of the Earth for thousands of years, and then shoots back up to the surface at temperatures of 143 degrees Fahrenheit, or 62 degrees Celsius. But changing rainfall patterns due to climate change are threatening this natural wonder!