Abu Dhabi Fossil Dunes: A frozen landscape created by climate change

Al Wathba, Abu Dhabi (CNN) — Drive an hour or so southeast out of the city of Abu Dhabi toward the emirate’s empty deserts and you’ll hit a landscape full of unexpected man-made creations.

The region of Al Wathba is home to a beautiful oasis-like wetland reserve created, so the story goes, by an overspill from a water treatment facility. Now it’s a lush terrain that attracts flocks of migratory flamingos.

Farther along roads lined with carefully planted trees, there’s the surreal site of an artificial mountain rising up on the horizon, its flanks buttressed by gigantic concrete walls.

And stray off the main roads onto the back lanes, you’ll encounter wide and dusty camel highways, where cooler evening temperatures see vast fleets of the humped beasts being exercised in readiness for the winter racing season.

But one of Al Wathba’s more unusual and elegant attractions is not the work of humans. Instead it’s been crafted over tens of thousands of years by elemental forces that, though they were at play millennia ago, offer insight into how the current climate crisis might reshape our world.

Abu Dhabi’s fossil dunes rise up out of the surrounding desert like frozen waves in a violent ocean made of solid sand, their sides rippling with shapes defined by raging winds.

‘Complex story’

The fossil dunes were formed over thousands of years.

Barry Neild/CNN

Though these proud geological relics have survived for centuries out in the middle of nowhere, they were opened as a free tourist attraction in Abu Dhabi in 2022 as part of efforts by the emirate’s Environment Agency to preserve them within a protected area.

Whereas Instagrammers and other visitors once needed all-terrain vehicles to ride up to the fossil dunes in search of a dramatic selfie backdrop, they now get a choice of two large parking lots that bookend a trail which meanders past some of the more spectacular landmarks.

Along the way are informative signposts that give some bare-bones information on the science behind the dunes’ creation — essentially, moisture in the ground caused calcium carbonate in the sand to harden, then powerful winds scraped them into unusual shapes over time.

But there’s far more to it than that, says Thomas Steuber, a professor in the Earth Science Department of Abu Dhabi’s Khalifa University of Science and Technology, who spent much of the Covid lockdown studying the dunes while unable to travel to other areas of geological interest.

“It’s a pretty complex story,” Steuber tells CNN.

Steuber says that generations of dunes were created by cycles of ice ages and thaws that occurred between 200,000 and 7,000 years ago. Ocean levels dropped when frozen water increased at the polar caps and during these drier periods, dunes would’ve built up as sand blew in from the drained Arabian Gulf.

When the ice melted, leading to a more humid environment, the water table rose in what is now Abu Dhabi and the moisture reacted with the calcium carbonate in the sand to stabilize it and then form a kind of cement, which was later whipped into ethereal shapes by prevailing winds.

Destructive forces

Power lines stride behind the dunes, adding another dimension to the scene.

Barry Neild/CNN

“The Arabian Gulf is a small basin that’s very shallow,” says Steuber. “It’s only about 120 meters deep, so at the peak of the ice age, about 20,000 years ago, there was so much piled up on the polar ice caps that water was missing from the ocean. That meant the Gulf was dry and was the source of material for the fossil dunes.”

Steuber says that the fossil dunes, which occur throughout the UAE and can also be found in India, Saudi Arabia and the Bahamas, likely took thousands of years to form. But, despite the official protection now offered in Abu Dhabi, the erosion that gave each its unique shape will also eventually lead to their demise.

“Some of them are quite massive, but in the end the wind will destroy them. They are essentially rocks, but you can sometimes break them with your hands. It’s quite a weak material.”

Which is why, at Al Wathba, visitors are now being kept some distance from the dunes, although still close enough to appreciate their impassive beauty.

Touring the site is best in early evening when harsh daytime light is replaced by a golden glow from the setting sun and the sky takes on the lilac hues of magic hour. It takes about an hour to stroll along the sandy path from the visitor center and souvenir stall to the parking lot at the other end — and about 10 minutes to shortcut back.

The untouched serenity of the dunes is contrasted at some points along the trail by a chain of gigantic red and white electricity pylons that stride over the horizon in the distance. Rather than spoil the scene, this engineering spectacle adds a dramatic modern dimension to a landscape otherwise frozen in time.

As dusk settles, some of the dunes are illuminated, offering a new way to view these geological marvels.

Religious clues

At night, the dunes are illuminated.

Department of Culture and Tourism — Abu Dhabi

“The dunes look really amazing,” said Dean Davis, visiting the site during a day off from work in Abu Dhabi city. “It’s nice they’re being conserved and the government has done a great job.”

Ashar Hafeed, another visitor touring with his family, said he was also impressed. “I saw it on Google and just needed to come and take a look,” he said, adding that “once was enough” to appreciate the dunes.

Stauber and his team from Khalifa University are likely to be repeat visitors though.

“We’re continuing to study them,” he says. “There are quite a few interesting questions about sea-level changes during the recent ice ages still to answer and it’s very important for understanding the current geomorphology of the coastline of the Emirates. It’s also obviously an analog for future sea-level change.”

And, says Steuber, the dunes could be evidence of the inspiration behind the tale of Noah’s flood, which features in the Koran, the Bible and the Torah, the texts of the three major religions to emerge from the Middle East.

“Possibly, this was the flooding of the Arabian Gulf at the end of the ice ages, because the sea level rise was very rapid.

“With a dry Arabian Gulf, the Tigris and Euphrates rivers would’ve discharged into the Indian Ocean and what is now the Gulf would have been quite a fertile low lying area which 8,000 years ago would’ve been inhabited, and people may have experienced this rapid sea level rise.

“Perhaps it led to some historic memory that made the holy books of these three local religions.”