There was standing water in puddles, colored by pink and orange halophilic bacteria. More bacteria, mostly green and pink, live in layers just under the salt crusts. They are using the salt crust like a greenhouse window. The salt lets some light through, but not too much. It also protects against desiccation, and limits competition from other organisms.
After collecting our samples and saying goodbye to
Cambridge High School, we continued south on this dead-end road into the Rub Al Khali, also known as the Empty Quarter. This is the world’s largest area of continuous sand dunes, stretching about 600 miles into . Jon Rask and I climbed a dune, and the heat was so intense it was hard to breathe. It was at least 30 degrees F hotter on the dune than it had been on the sabkha, and it was warm enough on the sabkha. Saudi Arabia