Nile Delta Poised to Be Sunk by Sea Level Rise - Groundwater Salinity Already a Growing Problem
photo: Kristina via flickr
Bangladesh may be the poster-child of global warming's perfect storm -- high population density, low-lying land, and an utter lack of funds for mitigation and adaptation -- but a great new piece in The Guardian really paints a vivid picture of another of the world's great deltas, just waiting to be devastated by climate change. Author Jack Shenker looks at the Nile Delta and the unfolding environmental disaster there:Delta is Source of 60% of Egypt's FoodLet's sum it up: The Nile Delta has a population density of 4,000 people per square mile and is home to two-thirds of Egypt's population of 83 million -- that's set to increase to 110 million in the next twenty years. The Delta is the source of 60% of Egypt's food. The vast majority is under one meter above sea level, with some areas actually below sea level -- meaning that even under conservative sea level rise predictions, by 2100 up to 20% could be entirely underwater.
Groundwater Salinity Strikes Before the Waves HitBut even today there are problems with salt water. Though sea level rise is a looming issue, increasing groundwater salinity strikes before the water itself arrives and isn't helped by current water use trends. Shenker tours the fields of one farmer and finds:
The rich brown soil has greyed out in recent years, leaving a barren salt-encrustation on the surface. The cause is underground saltwater intrusion from the nearby coast, which pushes up through the soil and kills off roots. Coastal farmland has always been threatened by saltwater, but salinity has traditionally been kept at bay by plentiful supplies of fresh water gushing over the soil and flushing out the salt. It used to happen naturally with the Nile's seasonal floods; after the construction of Egypt's High Dam in the 70s (one of the most ambitious engineering projects on earth), these seasonal floods came to an end, but a vast network of irrigation canals continued to bring gallons of fresh water to the people who worked the land, the fellahin, ensuring salinity levels remained low.photo: James Buck via flickrCrop Yields to Decline Up To 50% by 2040You think that's bad? It's estimated that over the next 50 years the amount of water reaching the delta, due to increased evaporation and increased demand upstream, is expected to decline 70% -- the effect being a 40% decline in wheat yields and a 50% decline in corn yields by 2040.
Today, however, Nile water barely reaches this corner of the Delta. Population growth has sapped its energy upstream, and what "freshwater" does make it downriver is increasingly awash with toxins and other impurities. Farmers such as Maged now essentially rely on waste water - a mix of agricultural drainage and sewage - from the nearby town of Sidi Salim.
The result is plummeting fertility; local farmers say that whereas their fathers spent just a handful of Egyptian pounds on chemicals to keep the harvests bountiful, they now have to put aside between 25 and 80% of their profits for fertilizers just to keep their crops alive.
That's just the tip of the of the problem. Check out the original for the full story: The GuardianGlobal Climate ChangeSea Level Rise Best-Case Scenario: 50cm Rise, 10% of World's Population HitBangladesh Tries Working With Nature to Stave Off Sea Level RiseWhen Population Growth and Resource Availability CollideClimate Change Already Expanding Tropics, Sub-Tropical Arid Zones and Disease