WATER SHORTAGE: City growth and climate change could leave more than one billion people without enough water by 2050, according to a new study.
Image: research.gov
Rapid urban growth and climate change will leave more than 1 billion urban dwellers with a water shortage by 2050, according to a study released last week.
Published in the Proceedings of the National Academy of Sciences, the study shows urban growth rates alone leaving 993 million city residents living on less than 100 liters of water a day. The effects of climate change add 100 million people to that toll. Rob McDonald, lead author of the study, said these numbers reflect current trends and are by no means definitive.
"Fast urban growth and climate change pose a challenge," said McDonald, a scientist with the Nature Conservancy. "It's a challenge that can be met and has to be met."
The 100-liter-per-day benchmark comes from the World Health Organization and the U.S. Agency for International Development. Both recommend it as the minimum amount for consumption in normal uses like bathing, drinking and cooking. In contrast, the average American uses 376 liters a day, although that number varies per region.
For the study, McDonald and six other scientists used a projected global population of 9 billion by 2050. That paints a picture of a world where one of every nine people lacks a reliable water supply. Currently, about 150 million people worldwide get by on less than 100 liters of water every day. The U.S. Census Bureau estimates the present world population at 6.9 billion.
Between now and 2050, the study projects the world will add 3 billion people in cities, most of them in developing areas in India, West Africa and China. That's roughly the equivalent of adding a city the size of Washington, D.C., to the world every week, McDonald said.
Much of this urban growth will occur in areas with seasonal water shortages. The study projects 3.1 billion people will be dealing with seasonal water shortages by 2050.
Shifting water away from agriculture?
McDonald identifies three elements essential to urban areas providing water to people. First, there has to be enough water nearby for a city to tap into. Second, an infrastructure needs to be developed that can bring that water to its people. Finally, that water has to be clean enough to drink. His study focuses on the first element, water availability.
While a shifting climate will change different environments in different ways, it will ultimately leave more people without water than before, according to the study.
"Some cities are going to get wetter, and some will get drier," McDonald said, "but [climate change] puts 100 million more in water-stressed areas."
Since most of the projected urban growth will happen in seasonally water-stressed areas, there's a wider range of solutions for the problem than there would be in dry areas like deserts, McDonald said.
Agriculture, the world's biggest water consumer, is also one of its the biggest wasters. The report recommends improving the industry's efficiency and cites previously successful approaches. One, in South Africa, had farmers remove plantations of non-native trees that require a lot of water to survive.
The report is a part of a series of studies from the National Center for Ecological Analysis and Synthesis examining the effects of urban growth. Its funding came from the National Science Foundation and the Nature Conservancy.
Reprinted from Climatewire with permission from Environment & Energy Publishing, LLC. www.eenews.net, 202-628-6500
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16 Comments
Add CommentSo is this before the Ice Caps melt and drown the coastal populations, and after the increased storm activity? Or is the timeline now saying there will be no gill-ed up Kevin Costner?
Reply | Report Abuse | Link to thisAt least I now know what happened to plot writers from Heroes Season 2.
No but seriously, water is a finite resource, and has already been scarce without the divine intervention of angry climate gods. You can tell here, since climate change is barely mentioned in this article on globalization and population growth.
Water isn't scarce. The problem is people trying to live where they shouldn't, and then growing the population as if they lived in an abundant belt of verdance. Agriculture can certainly be improved by not trying to grow tropical plants in the desert for instance.
Reply | Report Abuse | Link to thisMove to where the water and food are and stop trying to bring it to the desert.
If we go on the presumption that the technology of our cities infrastucture and planning are all just hunky-dory and things will just plod along like nothing ever changes we would be guilty of criminal negligence based on what we now know about the world in which we live. Whether the temps go up or down, or even stay the same, the world and its systems are dynamic and we are doomed if we build as if they were static, which is pretty much how all the classical cities and their subsequent reiterations have been since the very first cities appeared. Fortunately we know more and hopefully city planners will seek the advice of geophysicists and geomorphologists and competent design engineers and architects to build cities that take this modern perspective into consideration when they design the next generation of cities...but then again, I am an optimist, and history has shown that we have less than perfect vision when it comes to planning for the future even when we are fully aware of the consequences of our choices. That doesn't seem to be changing. Cheers.
Reply | Report Abuse | Link to this"climate change is barely mentioned in this article on globalization and population growth."
Reply | Report Abuse | Link to thisCorrect. Why would an article about an effect that may take place over the next few decades include statements about something that may take place over the next few centuries? Which climate effects are you talking about? The movie ones or the geologic ones?
What an attention grabbing headline!
Reply | Report Abuse | Link to thisUnfortunately it has nothing to do with the science of potential climate change, but it does appeal to the undereducated on the topic. If an area has too little water to support the population in that area, why don’t those people do something about it over the 40 year time period? Over 40 years, people can either migrate or build the proper infrastructure to support them. If they are to dumb to do either, then so be it.
Actions by the US will not impact this issue in any way. India is very corrupt and that is why they have so much difficulty in getting infrastructure built to protect their population. That is not the problem of the US or ours to solve.
Water shortages are becoming an increasing problem in Asia because, among other things, the glaciers are receding and weather patterns are changing, not because of corrupt governments. As local water shortages become more of a problem over time, people are not going to wait until the water runs out. They will simply migrate to areas where there still is sufficient water. This will lead to inevitable conflicts between the haves and have nots.
Reply | Report Abuse | Link to this@albee- You are 95% incorrect.
Reply | Report Abuse | Link to thisAs someone who does extensive business in SE Asia, I can tell you that the region is extremely corrupt and this corruption has a massive impact on infrastructure construction. If Indians and Pakistanis were to build dams and sewer systems there would be far less damage due to significant rainfall events and no water shortages. You fear the receding glaziers, but that is not a problem for humanity. A glazier may look pretty in a photo, but humans need the ice melted to use, and we need the land to grow things on. If dams were built downstream, there would be no water shortage issue.
"Move to where the water and food are and stop trying to bring it to the desert."
Reply | Report Abuse | Link to thisOooooh and this is where the fun starts ... I live in Mexico. I live in a city of 4 million people it hasn't rained here since July 2 2010 ..... where do you live amigo ;-)
By the way; you only need reply if you live in an abundant belt of verdance.
Reply | Report Abuse | Link to thisIf you live near the sea in a desert, you build desalination plants.
Reply | Report Abuse | Link to thisI live in the mountains where thanks to the floods of a couple of weeks ago and the rain that caused it, our drought may finally be ending. It's 77F right now and tomorrow we'll have freeze warnings again. That's the beautiful thing about weather, it changes!
If you overtax the resources of any area you're asking for trouble. Mother Nature WILL hold you responsible! Just look at the difference between Haiti and the Dominican Republic as an example.
Here's an idea for those so concerned with CO2. Stop clear cutting rain and other forests. Plant trees instead. Sounds a lot better and easier than seeding the upper atmosphere with sulphides to reflect sunlight as I saw yesterday as a possible 'plan B' to 'solve' global warming.
Steve--maybe the people in Mexico should stop their population growth and their water issues would be minimized.
Reply | Report Abuse | Link to thisPlanet earth is not governed by a one world government where everyone sings kumbia. What we have is close to 200 different nations competing for limited resources.
As this magazine is called Scientific American, from the American perspective- we can easily adjust to climate change as it evolves, we are a nation reducing our CO2 per capita emissions and no matter what we do, CO2 levels will go nowhere but up for at least the next 40 years. Even after new technologies result in worldwide CO2 emissions going down, CO2 will stay around for many decades before going down.
The key issue is simply building the right infrastructure to adapt. Nations that do so will flourish, those that do not proceed at their own peril. it is not the problem of Americans to fix it for them.
And not one mention of technologies to purify water that covers over 98% of this planet's surface?
Reply | Report Abuse | Link to thisThe problem is not shortage, it's over abundance of water where we least need it: IN THE OCEANS.
Water. Water every where and not a drop to drink. Water is a scarce resource that it should be treated like gold, for without water life could not continue on this planet for long. We have a finite amount of drinkable water and a growing population that is outpaceing our natural resources. We are the first species in the history of our planet that is destroying the natural ecology of the planet; deforestation, overpopulation, resource depletion and pollution. We are becoming a species that is more and more urban, but the of urbanization has to be replaced by a new eco-friendly . Since we know what the problems are, what are the solutions?
Reply | Report Abuse | Link to thisCome on guys. It kills me to see Scientific American continue the slide from a highly respected science magazine to a sensationalist rag. Demands on fresh water sources have always been a problem somewhere and they always will be. And water is not a finite resource. Entrophy Law notwithstanding we try as hard as we might to dirty our water and God has set it up perfectly to be purified and returned to us by the billions of gallons. Where's your faith, man?
Reply | Report Abuse | Link to thisKristi276- Your question about solutions really depends upon your perspective. I believe solutions need to be formulated by individual nations.
Reply | Report Abuse | Link to thisAs best as we know it today, additional human caused CO2 will warm the planet over a span of many decades. It is still unsettled as to what specific amount of additional CO2 will lead to in terms of a temperature rise. Regardless, the temperature rise is really not nearly as important as the potential change to weather patterns and specifically to changes in rainfall patterns. This will be the great potential change for humans. Most in the science community believe that a warmer world will mean somewhat more rainfall overall, but some areas will get less.
For any specific local area, the solution to climate change is the construction of proper infrastructure to store fresh water in sufficient quantities for humans to use in spite of potential longer periods of drought. Additionally, local communities need to plan and construct sewage and flood control systems to mitigate damage from potential flooding when heavy rainfall occurs.
On a longer term perspective, nations need to limit their population growth. Many countries have absolutely unsupportable growth curves that need to be changed.
The concept that wealth should be essentially transferred from countries like the United States to countries less developed and overpopulated is not likely to be well received by the citizens of the USA.
There's more to water availability than just living in an area with precipitation. I live near the Fraser River west of Denver. We get a reasonable amount of rain and lots of snow (30 feet in a normal winter). The Fraser River (the first significant tributary to the Colorado River) would have lots of water in it if 80% of it wasn't owned by Denver Water. Most of "their" water is being pumped across the continental divide to Denver and is used to create bluegrass lawns which are completely unnatural in a high desert like Denver. The small amount of water that remains where it would naturally be is insufficient to keep the river, its ecosystem and surrounding valley alive.
Reply | Report Abuse | Link to thisDenver's purchase of water rights 100 years ago gave them the legal right to suck our part of Colorado dry. Does it give them the moral right to do so? Don't try to defend these trans-basin diversions of water by saying that the cities need it: About 60% of Denver's water consumption is used for residential irrigation.
What about other parts of the world? If China, Iraq, India or Pakistan can move water from one region to another to supply the demands of the richer area is that always a good thing? If Las Vegas, Phoenix, Denver and Los Angeles can afford to dry up the Colorado and other rivers do we as a nation feel that it's the right thing to do? Other nations need to look carefully at their water-related decisions.
There are no simple answers. Simply saying "move the water to where it's needed" is naive. Isn't it needed where it already is? Is it more needed to preserve the natural environment in one place or to create an unnatural environment somewhere else? If cities in the desert (like those mentioned earlier) got over trying to create the illusion that they are supposed to be lush and green like Kentucky we'd be much better off. Embrace your area's natural environment; don't remake it into something it was never meant to be. If we all do there will be more water for people, plants and animals that actually need it.