How Much Water is on Earth?

The US Geological Survey (USGS) recently published a remarkable image helping us appreciate the preciousness of water. We have all probably heard the oft-quoted statistic that about how 70 percent of the Earth’s surface is water-covered – most of it in the form of oceans. Though it sounds like a lot, if we gathered all that water up, how much space would it take up?  The USGS, in the image below, shows us that the answer is… not much.

global water volume, USGS, earth water
click for larger image (Illustration by Jack Cook, Woods Hole Oceanographic Institution (©) Howard Perlman, USGS)

Though about 97% of Earth’s water is in the form of oceans, these oceans are shallow compared to the Earth’s radius – just a couple miles deep.  The image above shows us just how shallow the oceans are, using radar image data, mapping the bottom of the ocean. The blue sphere shows what would be required to contain all Earth’s water – from oceans, lakes, rivers, glaciers, snowpack, etc. The sphere has a radius of just 700 kilometers.

When this picture appeared in the news, I found myself wondering what portion of that sphere was fresh water. I noted a number of reader comments asking the same thing. It’s an important question. The Food and Agriculture Organization of the United Nations (FAO) projects that two-thirds of the planet will be water stressed by 2025.  Safe drinking water and abundant water for irrigation will become increasingly scarce.

So what size sphere would be required to hold all the accesible fresh water in the world? The picture below shows the answer.  But first, using USGS water data, let’s look at how the size of that fresh water sphere was calculated:

The Math:

  • As the USGS demonstrated, all Earth’s water (1,386,000,000 cubic kilometers) can be contained in a sphere with radius of about 693 kilometers.
  • Of that water, only about .77% is fresh water, usable by humans (ground water, lakes, rivers, etc.)  N.B.: An additional 1.74% of global water is stored as glaciers, ice caps and permanent snow, but is not accessible and usable.
  • .77% x 1,386,000,000 cubic kilometers = 10.7 million cubic kilometers of fresh water
  • 10.7 million cubic kilometers of fresh water = a sphere with radius of 137 kilometers

Here’s the updated image, with spheres representing “All Water” and “Fresh Water” – side by side.

total water and total freshwater on earth
(source: USGS data, 8020 Vision calculations)

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Last Call at the Oasis

Last Call at the Oasis just opened in movie theaters this past Friday. Film critic Christopher Campbell said it best: Last Call at the Oasis is “necessary viewing for anyone on the planet who drinks water.

It helps us understand how water is central to every part of our lives, shows how it is becoming more scarce and in some cases toxic, and offers examples of ways to conserve water more effectively, reduce pollution, and manage our precious water resources better.

The movie trailer is below.  As you watch it, note the lake that appears at 45 seconds in to the trailer.  That is Lake Mead.  It is the main source for water to Las Vegas, and feeds the Hoover Dam, which generates electricity for Las Vegas and beyond. The lake has been around for a very very long time, and, according to Scripps Institution of Oceanography, will likely be dry in the next 10 years.  Increased consumption and changing climate have caused the lake to drop an average of 10 feet per year. In 4 years, the water level will likely drop so low that Hoover Dam will be unable to operate.

Here’s a picture of Lake Mead taken in 2007.  It was bad then and it’s worse now.

Lake Meade water scarcity
A picture of Lake Meade taken in 2007

I was driving through Texas last summer, and all the radio stations could talk about was how hot and dry it was.  At that time, Austin had over 70 days straight of temperatures above 100 degrees F.  Wildfires raged as the drought-parched land baked to a crisp. Here’s a drought map that shows just how extensive the drought was.  Note that the brownish-red areas are ranked as “Exceptional” – beyond even extreme drought.

Water - US Drought Map, Texas drought
Record Texas drought in 2011

As climate change continues its slow inexorable advance, we should expect to see the southern US trend much drier and hotter.  Agriculture and ranching will become unsustainable.  Humans will need to be very good at conserving and getting by with much less water. Last Call at the Oasis is a wakeup call.

Here’s the movie trailer for Last Call at the Oasis

Consider seeing the movie. It helps us understand how we can preserve our precious water resources. It is so much more satisfying being part of the solution, than being part of the problem.

Recommended Reading

Water Scarcity in the US

The Real Population Problem

Congress Releases Report on Toxic Chemicals Used In Fracking

Peñon de los Banos, a women-owned farm cooperative

The women of Penon de los Banos farm cooperative, Mexico
The women of Penon de los Banos farm cooperative, Mexico

Peñon de los Banos, is a women-owned sustainable organic farm cooperative, a short ride from the mountain town of San Miguel de Allende, Mexico. My wife and I are part of a field trip, organized by The Center for Global Justice, visiting the Campo, to learn more about their work.

Residents of this small dairy farm have been part of a traditional ejido system for generations. Ejidos are communal lands, for growing food, shared and co-managed by the people of the community. The system was developed during ancient Aztec rule of Mexico. The North American Free Trade Agreement (NAFTA) has forced the Mexican government to do away with the ejido system, and open the land up to foreign agri-business.

With exponential population growth driving increasing demand for food, food prices are increasing. Farm land has become a growth investment. Foreign investors are eager to buy up land in this fertile region. This can put land ownership out of reach for local farmers. Much of the traditional farming is now being forced out, replaced by industrial agriculture. So, the women of Peñon de los Banos have banded together and formed a SPR (Sociedad de Produccion Rural). Adding to their dairy cow farm, they have constructed nine greenhouses to grow organic tomatoes and other vegetables, year round. They endeavor to farm sustainably, using composted manure from their cows to keep the soil fertile, and employing drip irrigation to conserve precious water. They are creating value-added products including tomato sauce and paste.

If they can grow the farm business, they hope to bring their husbands into the operation. To help pay the bills, the spouses have had to leave the community, to work in San Miguel or the US.

They are surrounded by industrial farming, which presents some challenges. The industrial farming methods use old fashioned wasteful irrigation techniques. Peñon de los Banos uses very efficient drip irrigation, but they are drawing from the same well and aquifer as the industrial farms, so if the industrial farms run the well aquifer dry, it effects Peñon de los Banos too. And with increased drought in the south, water is getting very scarce. Also, the industrial farms are not organic, and when they spray with pesticides, the women at Peñon de los Banos need to quickly cover their crops so the poisons don’t settle on the crops.

This trip has a special energy, as we were accompanied by a wonderful bunch of young women and their teachers, from Edgewood College, in Madison, Wisconsin. The students are here on a trip lead by their sociology professor, Julie Whitaker. They are a fantastic bunch of people. Julie and I talk about sustainable farming challenges facing farmers. She seems like a great teacher. Her students ask great questions. I continue to be impressed with the social engagement and energy young people are bringing to our world. These students rock! They have it in them to leave the world a better place.

After the tour, the women of the farm serve us a delicious traditional lunch (comida). They teach me how to make gorditas, toasting them on a wood fire heated steel plate. I am frankly overwhelmed by their beautiful generous spirit. For me, this has been the highlight of my month in Mexico.

Here is a video interview with the women of Peñon de los Banos, pictures from the trip, and an audio presentation by Cliff Durand of The Center for Global Justice. Cliff talks about the history of Peñon de los Banos and small farming in Mexico, and talks about the recent impact NAFTA is having on small farmers.

Video – filmed at Peñon de los Banos

Includes video of traditional mid-day meal (comida) and interview with the women that run the farm cooperative. Translation is provided by Ousia Whitaker-DeVault.

Pictures – from around Peñon de los Banos

Scenes from the farm, sharing a mid-day meal, and at the organic farmers market

Greenhouse at Penon de los Banos farm cooperative, Mexico
One of eight greenhouses on the farm
Cows at the dairy at Penon de los Banos farm cooperative, Mexico
Cows at the dairy at Penon de los Banos farm cooperative, Mexico
Comida - Sharing a meal with the women of the cooperative farm at Penon de los Banos, Mexico
Comida - Sharing a meal prepared by the women of the cooperative farm at Penon de los Banos, Mexico
Cooking gorditas at Penon de los Banos farm cooperative, Mexico
Cooking gorditas at Penon de los Banos farm cooperative, Mexico
The women of Penon de los Banos farm cooperative, Mexico
The women of Penon de los Banos farm cooperative, Mexico
Farm dogs at Penon de los Banos farm cooperative, Mexico
Farm dogs at Penon de los Banos farm cooperative, Mexico
Horse-drawn cart at Penon de los Banos farm cooperative, Mexico the farm.
Horse drawn cart on the farm.
saturday organic farmers market in San Miguel de Allende, Mexico
Saturday organic farmers market in San Miguel de Allende, Mexico

Audio Presentation: Small farming in Mexico

Cliff Durand, of The Center for Global Justice gives background on small farms in Mexico and the effects of NAFTA. Audio quality is low until about 1 minute 30 seconds. Duration: 57 minutes.

Recommended Reading: The Coming Famine

Keywords: Julian Cribb, The Coming Famine, food, water, population, climate change

If you are a regular reader of this blog, you know that we track several core issues that we believe will have profound impact on us all – rich and poor, individuals, communities, business, and government. They are population, energy, water, food, climate change and healthcare. In a sense, food interrelates to all the other issues – it takes tremendous energy and water to produce our food, climate change will reduce food production, and food choices affect our health.

An excellent new book has just been published that clearly and concisely lays out the global food challenges unfolding around us and details what to do about it. The book is The Coming Famine: The Global Food Crisis and What We Can Do to Avoid It by Julian Cribb. The NY Times has an excellent excerpt and leads with this compelling quote:

Lo que separa la civilización de la anarquía son solo siete comidas.
(Civilization and anarchy are only seven meals apart.)

—Spanish proverb

Food, water, shelter and security are the fundamental building blocks of  a persons survival. When those basics are removed, even for a few days, a civilized population can move toward anarchy in a heartbeat.

Maslow's Hierarchy of Needs - from thrive to survive

Rather than highlight the NY Times excerpt, I think it is worth looking at the solid concise description Cribb provides, of the main drivers challenging the supply and demand sides of food production. If you read nothing else in this book, read this and remember it as you  try to make sense of the news stories realted to food that will become more common as the crisis deepens.

Excerpt of The Coming Famine by Julian Cribb

To see where the answers may lie, we need to explore each of the main drivers. On the demand side the chief drivers are:

Population. Although the rate of growth in human numbers is slowing, the present upward trend of 1.5 percent (one hundred million more people) per year points to a population of around 9.2 billion in 2050 — 3 billion more than in 2000. Most of this expansion will take place in poorer countries and in tropical/subtropical regions. In countries where birth rates are falling, governments are bribing their citizens with subsidies to have more babies in an effort to address the age imbalance.

Consumer demand. The first thing people do as they climb out of poverty is to improve their diet. Demand for protein foods such as meat, milk, fish, and eggs from consumers with better incomes, mainly in India and China but also in Southeast Asia and Latin America, is rising rapidly. This in turn requires vastly more grain to feed the animals and fish. Overfed rich societies continue to gain weight. The average citizen of Planet Earth eats one-fifth more calories than he or she did in the 1960s — a “food footprint” growing larger by the day.

Population and demand. This combination of population growth with expansion in consumer demand indicates a global requirement for food by 2050 that will be around 70–100 percent larger than it is today. Population and demand are together rising at about 2 percent a year, whereas food output is now increasing at only about 1 percent a year.

These demand-side factors could probably be satisfied by the world adopting tactics similar to those of the 1960s, when the Green Revolution in farming technology was launched, were it not for the many constraints on the supply side that are now emerging to hinder or prevent such a solution:

Water crisis. Put simply, civilization is running out of freshwater. Farmers presently use about 70 percent of the world’s readily available freshwater to grow food. However, increasingly megacities, with their huge thirst for water for use in homes, industry, and waste disposal, are competing with farmers for this finite resource and, by 2050, these uses could swallow half or more of the world’s available freshwater at a time when many rivers, lakes, and aquifers will be drying up. Unless major new sources or savings are found, farmers will have about half of the world’s currently available freshwater with which to grow twice the food.

Land scarcity. The world is running out of good farmland. A quarter of all land is now so degraded that it is scarcely capable of yielding food. At the same time, cities are sprawling, smothering the world’s most fertile soil in concrete and asphalt, while their occupants fan out in search of cheap land for recreation that diverts the best food-producing areas from agriculture. A third category of land is poisoned by toxic industrial pollution. Much former urban food production has now ceased. The emerging global dearth of good farmland represents another severe limit on increasing food production.

Nutrient losses. Civilization is hemorrhaging nutrients — substances essential to all life. Annual losses in soil erosion alone probably exceed all the nutrients applied as fertilizer worldwide. The world’s finite nutrient supplies may already have peaked. Half the fertilizer being used is wasted. In most societies, up to half the food produced is trashed or lost; so too are most of the nutrients in urban waste streams. The global nutrient cycle, which has sustained humanity throughout our history, has broken down.

Energy dilemma. Advanced farming depends entirely on fossil fuels, which are likely to become very scarce and costly within a generation. At present farmers have few alternative means of producing food other than to grow fuel on their farms — which will reduce food output by 10–20 percent. Many farmers respond to higher costs simply by using less fertilizer or fuel — and so cutting yields. Driven by high energy prices and concerns about climate change, the world is likely to burn around 400 million tonnes (441 million U.S. tons) of grain as biofuels by 2020 — the equivalent of the entire global rice harvest.

Oceans. Marine scientists have warned that ocean fish catches could collapse by the 2040s due to overexploitation of wild stocks. Coral reefs — whose fish help feed about five hundred million people — face decimation under global warming. The world’s oceans are slowly acidifying as carbon dioxide from the burning of fossil fuels dissolves out of the atmosphere, threatening ocean food chains. Fish farms are struggling with pollution and sediment runoff from the land. The inability of the fish sector to meet its share of a doubling in world food demand will throw a heavier burden onto land-based meat industries.

Technology. For three de cades the main engine of the modern food miracle, the international scientific research that boosted crop yields, has been neglected, leading to a decline in productivity gains. Farmers worldwide are heading into a major technology pothole, with less new knowledge available in the medium run to help them to increase output.

Climate. The climate is changing: up to half the planet may face regular drought by the end of the century. “Unnatural disasters” — storms, floods, droughts, and sea-level rise — are predicted to become more frequent and intense, with adventitious impacts on food security, refugee waves, and conflict.

Economics, politics, and trade. Trade barriers and farm subsidies continue to distort world markets, sending the wrong price signals to farmers and discouraging investment in agriculture and its science. The globalization of food has helped drive down prices received by farmers. Speculators have destabilized commodity markets, making it riskier for farmers to make production decisions. Some countries discourage or ban food exports and others tax them, adding to food insecurity. Others pay their farmers to grow fuel instead of food. A sprawling web of health, labor, and environmental regulation is limiting farmers’ freedom to farm.

The collapse in world economic conditions in late 2008 and 2009 has changed the prices of many things, including land, food, fuel, and fertilizer — but has not altered the fact that demand for food continues to grow while limits on its production multiply. Indeed, the economic crash exacerbated hunger among the world’s poor, and has not altered the fundamentals of climate change, water scarcity, population growth, land degradation, or nutrient or oil depletion.

As Cribb astutely points out, as developing nations become more affluent, they consume more protein, in the form of fish, meat, milk, eggs, etc.

Meat Protein Consumption in US and China
(source: US Department of Agriculture)

That protein is produced with grain, and it is an inefficient process:

  • It takes 1,ooo tons of water to produce a ton of grain
  • It takes about 15 pounds of grain to produce a pound of beef
  • It takes about 5,200 gallons of water to produce a pound of beef

Thinking about the Butterfly Effect – the idea that a butterfly flapping its wings in one part of the world, changing patterns in the air, can cause a tornado in another part of the world – we can see that famine in one part of the world becomes a kind of super butterfly. All nations – rich and poor – will feel the impact.

Cripp summarizes the challenge and frames the solution:

To sum it all up, the challenge facing the world’s 1.8 billion women and men who grow our food is to double their output of food — using far less water, less land, less energy, and less fertilizer. They must accomplish this on low and uncertain returns, with less new technology available, amid more red tape, economic disincentives, and corrupted markets, and in the teeth of spreading drought. Achieving this will require something not far short of a miracle.

Yet humans have done it before and, resilient species that we are, we can do it again. This time, however, it won’t just be a problem for farmers, scientists, and policy makers. It will be a challenge involving every single one of us, in our daily lives, our habits, and our influence at the ballot box and at the supermarket.

It will be the greatest test of our global humanity and our wisdom we have yet faced.

Climate Change, Food, and Wildfires

Price of WheatAn article in the New York Times (Russia, Crippled by Drought, Bans Grain Exports) details Russia’s struggle with severe drought. Though any particular instance of drought can’t be directly linked to climate change and global warming, the world is warming, and instances of drought and associated wildfires, water shortages and crop loss are trending up.

The article highlights the tight coupling between food, water, and a warming world. It also shows how one countries problem affects us all, for example, Russia’s ban on grain exports has doubled the price of wheat worldwide.

For more on climate change and impact on food, see:

NOAA: June, April to June, and Year-to-Date Global Temperatures are Warmest on Record

State of the Climate: Hottest Decade on Record

Water Scarcity in the US

Climate Change May Reduce Protein in Crops

Highlights of the article – Russia, Crippled by Drought, Bans Grain Exports

  • Prime Minister Vladimir V. Putin on Thursday banned all exports of grain after millions of acres of Russian wheat withered in a severe drought, driving up prices around the world and pushing them to their highest level in two years in the United States.
  • Russia is suffering from the worst heat wave since record-keeping began here more than 130 years ago.
  • The export ban was widely seen as one of a series of populist moves by Mr. Putin to address rising resentment over the calamitous heat wave and the fires it has spawned.
  • Wheat prices have soared by about 90 percent since June because of the drought in Russia and parts of the European Union, as well as floods in Canada, and the ban pushed prices even higher. Exports from Ukraine, another major exporter, are down sharply this year.

Interactive Climate Map from Google Shows Future Impact of Climate Change

Using Google Earth, the UK Foreign Office (FCO) and the Department of Energy and Climate Change (DECC) have released an interactive climate map that provides insight on the impact of climate change around the world.

The Google Earth map shows how the world would be affected by a global average temperature increase of 4C. It illustrates rising water levels and reduced crop yields in different parts of the world if temperatures are not curbed by cutting greenhouse gases.

The map service is directed at a global audience; it details the work of the scientists working in countries across Asia, Latin America and Africa. It uses Met Office data, and will also feature Foreign Office’s own work on the economics of climate change that it has been doing with the likes of the Asian Development Bank. The map is interactive, allowing you to roam the planet and explore projected impact and view video providing climate scientists and researchers discussing impact details.

Articles detailing the project can be found at The Telegraph and the Financial TImes.  The online map is available here. If you don’t have Google Earth installed, you can download a copy here.
Climate Change Impact