Global Study Series, Part 2: Climate Makes and Breaks Civilizations: Lessons Learned on the Nile
By R. Bruce Hull
For almost five millennia, from ~10,000 years ago to ~5,000 years ago, the land that is now Egypt was lush and fertile, dotted with lakes, and abundant with wild food that supported human settlements, domesticated livestock, and nomadic hunters and gatherers. The enormous accomplishments of Egyptian civilization—Giza pyramids, Luxor temples, King Tutankhamun’s mummy—emerged because the climate changed, essentially ending rainfall, drying up lakes, and killing vegetation. Humans relocated out of necessity to the one reliable source of water, settling along the shores of the Nile. The world’s longest river, it is fed by monsoon rains falling hundreds of miles away, which are sensitive to climate conditions thousands of miles away.
Predictable annual flooding of the Nile brought fresh, moist, fertile soil. People planted and became dependent upon crops they could irrigate, store, and feed to livestock. Easy navigation by boats (it is possible to row or sail upstream from the Mediterranean Sea to the Aswan cataracts) facilitated sharing crafts, food, information, culture, and technology. Neighboring villages competed for resources and dominance. Wealth and power eventually consolidated into a hierarchical society spanning all of modern-day Egypt and beyond, a society capable of engineering, administrative, and artistic accomplishments that now attract millions of tourists and still confound archeologists.
Today, virtually all of Egypt’s agriculture depends upon Nile water, as do most of its industries and municipalities. Minimal and infrequent rains cannot sustain crops or replenish aquifers. Gleaning water from desalination is possible along two coasts, because Egypt’s vast reserves of natural gas and sunlight provide the power this energy-intensive process requires, but it is not practical to transport that water to where most people live and most food is grown. Water from the Nile will remain indispensable to Egypt’s survival.
What happens when the life-sustaining Nile flows diminish, become unreliable, or even dry up? Nearly 100 million Egyptians live along the narrow ribbon of life cutting through an otherwise brutally parched and infertile desert. Few modern societies could be more dependent upon such a vulnerable natural resource.
Much of the Nile begins as monsoon rains in the mountains of Ethiopia, Uganda, and other headwater countries. These monsoons will be disrupted by warming seas, melting glaciers, changing ocean currents, deforestation, and other rapidly changing global conditions. Predictive models about the impacts of future climate change on Nile flows are highly uncertain. Increasing and increasingly intense rain in the headwaters of the Blue Nile and White Nile tributaries are possible because warmer air carries more moisture. But even then, downstream flows will likely decline—perhaps dramatically—for three reasons:
- Hotter temperatures will accelerate evaporation.
- Increasing population, agriculture, and wealth in upstream countries will significantly increase water withdrawals.
- And, most consequentially, weather will be more variable, alternating between years of extreme flood and drought. Most worrisome, droughts will likely increase in severity and frequency, significantly diminishing downstream flows in drought years.
What will Egyptians do when the source of their food and economy evaporates? Where will they go? Millennia ago, a changing climate set ancient Egyptian civilization on a new course, creating some of humanity’s greatest accomplishments. Climate changes to come might produce some of humanity’s darkest hours.
Dr. Hull is a Senior Fellow at Virginia Tech’s Center for Leadership in Global Sustainability in Arlington and a professor at VT’s College of Natural Resources and Environment in Blacksburg. He writes and teaches about leadership for sustainable development and how to have influence in the cross-sector space where government, business, and civil society intersect. He advises organizations, communities, and professionals responding to the Anthropocene. He has authored and edited numerous publications, including two books, Infinite Nature and Restoring Nature. Currently, he serves as president of the Board of Directors of Climate Solutions University and on the advisory council for Virginia Tech’s Global Change Center.