https://www.unenvironment.org/news-and-stories/story/how-climate-change-and-population-growth-threaten-egypts-ancient-treasures
In his 40-something years as an archaeological excavator on Luxor's West Bank, Mustafa Al-Nubi has witnessed a flurry of changes.
Tourist numbers have surged, fallen, and then slowly grown again. Local villages have exploded in size. Even the landscape has undergone a radical transformation, as Egyptologists slowly pick their way through the vast Theban Necropolis. "It's like one big museum now," Nubi says. "My grandfather would not recognize his own house."
Yet none of this, he insists, compares to the unusual weather that's gripped southern Egypt in recent years. Where once he could work much of the dig season – usually from October to April – without breaking a sweat, now his traditional galabeya robe is often stained dark by 10am. Winter can be chilly one day, and stifling the next. Amid periodic downpours at unusual times of the year, Nubi and his colleagues have almost got used to dashing for cover. "I don't know what's happening," he said. "But it was not like this before."
The millennia-old treasures tell a similar tale. For much of history, conditions around Luxor were almost calculated to preserve its trove of pharaonic riches. With little rain, low humidity, and piles of swirling desert sand that cocooned the ancient temples in a protective bubble, there were few climatic concerns. And with a comparatively small local population, here on a previously isolated stretch of the Nile, there was little reason to suspect that the likes of the Ramesseum might go the way of their crumbling counterparts in densely populated northern Egypt. The pharaohs called their massive mortuary temples the temples of a million years; they were meant to last forever.
All that, however, is slowly beginning to change. Increasingly erratic weather that many largely attribute to climate change is eating away at the ancient stones. At the same time, booming population growth is complicating preservation efforts. After surviving thousands of years of war, invasion, and cannibalization for building materials, the splendours of ancient Egypt might have finally met their match. "We have a fear," said Mostafa Ghaddafi Abdel Rehim, a senior antiquities official in Luxor. "Like all the world, we have a fear of climate change."
Changing conditions
It starts with the temperature. The temple-heavy expanses of Egypt have always been sizzling during the summer, but it was never this hot – or for this long, both locals and archaeologists say. Some excavation days have had to be cut short, as overheating workers wilt in the exposed digging trenches. In other instances, changing conditions have even forced archaeologists to alter the way in which they document the hieroglyph-dotted walls. "We used to make blueprints using natural sunlight, but starting about 20 years ago, we found it harder and harder to burn the image onto the paper," said Ray Johnson, director of the University of Chicago's Epigraphic Survey, which has been working at Madinat Habu temple for almost 100 years. "It was then that we realized that it was getting hazier and hazier." At Karnak, the gargantuan New and Middle Kingdom complex that dominates the northern approach to Luxor, blindingly bright sunshine has already robbed most of the walls of their color, leaving tourists to crane their necks up at the sheltered ceilings.
Even more worryingly, soaring summer highs also appear to be leaving their mark on the building blocks themselves. Around Aswan, several hours train ride south of Luxor, temperatures that sometimes rise well over 40 C are slowly cracking many of the rose granite structures. The granite expands in the daytime sun, and then contracts overnight in the cooler air. "It can look like a bag of wool. It gets rounder and rounder, and then eventually breaks away," said Johanna Sigl of Cairo's German Archaeological Institute. On her dig site at the bottom tip of Elephantine island, mid Nile, several inscriptions, including one in which a senior official records his duties collecting stone for his pharaoh, have more or less disappeared as a consequence.
The effects of climate change will only get more intense, experts say, possibly requiring some tricky decisions about the viability of maintaining vulnerable historic sites.
"In some instances these places are the foundations of a tourism industry that brings a lot of benefits to the local people," said Mette Wilkie, Director of the Ecosystems Division at UN Environment. "But then you have a lot of buildings that are in the middle of nowhere, and here the situation is much more difficult."
The greatest damage, however, is seemingly done during winter. Though still rare, increasingly frequent downpours are savaging ancient mud brick buildings, most of which have only lasted so long because of limited rain. "Every year, we notice this is more of a problem," said Christian Leblanc, head of the French Archaeological Mission at West Thebes, who's directed conservation efforts at the Ramesseum for over 25 years. "Of course it degrades the stone." Particularly vulnerable are the temple's half dozen arched mud brick granaries, some of the largest remaining structures of their kind, which are periodically layered with new mud bricks to shield the originals from the elements.
In 1994, a monster storm illustrated the devastation rain can wreak. Hundreds of tombs, including many in the Valleys of the Kings and Queens, were swamped, the Temple of Seti I morphed into a lake, and hundreds of traditional mud brick houses collapsed. At Deir al-Bakhit, an early Christian monastery, the rain fell so furiously that it punched drop-shaped imprints into the mud brick. Wary of a repeat and fed up with frequent water-related repairs, most locals have since rebuilt in concrete.
Human impact
And then there's the direct environmental impact of human activity. Until the late 1960s, the Nile burst its banks every August, inundating the valley for miles on either side. These were the conditions that the ancient architects knew, and they factored them into their designs accordingly. But after the completion of the Aswan High Dam, the annual flood ended, and with it came a glut of new problems for the temples. Without the regular "cleanse", there's no longer anything to clear the salt from the topsoil.
"It eats away at the stone like an acid," Ray Johnson said. And with more humidity, in large part because of the enormous quantities of water evaporating off the dam's reservoir, there's more crystallization, as the salt particles in the temples' sandstone blocks expand. "So the lower walls of almost all temples are missing and filled instead with a kind of breathable mortar," Johnson added. From the toes of the Colossi of Memnon, the 700-ton statues of the pharaoh Amenhotep III, to the periphery of Karnak's Sacred Lake, faint white saline traces betray the danger at hand.
Population growth, too, has levied a heavy toll. More people means more agriculture, and so instead of the fields around the temples lying dry and fallow for part of the year as they once did, they're now under constant cultivation. It's raised the water table throughout the East and West Banks (hydrologists suspect that the dam has also played a part), and swamped the foundations with far more water than they were designed to handle.
"Just look, there are people and water everywhere," Christian Leblanc said. Many of the central pylons of Luxor Temple, the most centrally located of the great sites, have had to be patched up with cement after the fast-expanding city's sewage percolated upwards. As Egypt's numbers surge, already leaping from about 66 million in 2000 to over 95 million now, the pharaonic treasures are having to share their space with ever more houses and sugar cane crops.
"This is a phenomenon across the world, and there will be some areas where we will simply have to give up using land for our livelihood," Mette Wilkie said. UN Environment is working to tackle climate change and environmental degradation by helping countries embrace low-emissions growth; supporting the sustainable management of forests and other ecosystems; and finding innovative new ways to fund climate action. UN Environment also helps countries adapt to the changing climate, and build their resilience to future challenges.
In Egypt, there is some cause for optimism. In fact, officials have more or less resolved the groundwater issue for the time being. With funding from the U.S. Agency for International Development, the Ministry of Antiquities has installed an extensive drainage network around the key sites, which has seemingly lowered their water levels by up to four meters.
"It has been a big success. The problem is fixed," said Mohammed Abdelaziz, the ministry's top official in Upper Egypt. Authorities have ringed many of the antiquities' zones with walls to prevent further urban or agricultural encroachment, and established four field schools in the Luxor area to teach inspectors how to better treat the treasures and identify potential threats. All this coming at a time of new technological innovations has made some archaeologists quite bullish about the temples' long-term prospects.
Just to be on the safe side, though, others have stepped up their documentation efforts. If worse comes to the worst, at least we'll have a record of what's been lost. "There is more urgency now," Ray Johnson said. "That's why we go first to what's most threatened."
Read more about UN Environment's work on climate change.
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