y. over two billion people still live without safe drinking water in their homes. the average american flushes more water down the toilet than most africans use every day. worldwide, poor water sanitation kills nearly a million people every year. the threat to cape town came and went. in may 2018, the three-year-old drought was over. -[laughter] -[indistinct chatter] [indistinct chatter] [chiwetel] they prayed for rain and the rain came. the whole city celebrated. [man] so having analyzed the new data, we are now in a position

to state that we have not only managed to avoid day zero this year but we can also safely get through the summer of 2019. [chiwetel] water flowed back into the rivers, the dams filled up, cape town had been saved but for how long? [anthony] to simply assume that the next rain is going to suddenly wash all your problems away is, in my view, suicidal. unfortunately, the day zero debate only focuses on, on water for baths, water for toilets, water for drinking, water for showers. domestic water. thats not the significant water. there's water for the economy. theres water to sustain jobs. theres water for tourism. theres water for agriculture, for the food that we eat. thats big water. so there is no economic future based on the business as usual approach.

[chiwetel] scientists do not expect the earth to run out of water any time soon. the total amount of fresh water hasn't changed since the age of the dinosaurs. the pattern of human civilization, the great cities, agriculture, power plants, all the infrastructure of life on earth, has been determined by the availability of water. but the patterns of water availability are shifting. the evidence from space shows that while in some regions, the water supply remains stable, in others, there are unsettling fluctuations.

the world's wetlands, in the tropics and the extremely high latitudes are getting wetter. [digital bleeps] the dry areas in between are becoming drier. too much water, or too little, either way, these fundamental shifts can be devastating. [digital bleeps] [gentle guitar music plays] [mike] my name is mike callicrate. we're in st. francis, kansas. we raise cattle and hogs and we have some chickens for eggs. and we basically produce food. [gentle guitar music plays] [chiwetel] mike callicrate is a country boy through and through. born third of eight children

to a family that had been farming on the plains since the early 1900s. his dad and his granddad had been farmers and mike was never going to be the one to change anything. -[guitar music plays] -[cheering and hollering] [mike] i started riding bulls when i was in high school. id go to high school rodeos and then it was an easy transition to want to go to college and rodeo in college. i not only was a bull rider and could make money rodeoing but i made the bull ropes that the bull riders use to, to hang onto. i ended up being one of the top three bull rope makers in the country. [chiwetel] this is calicrate country, the high plains, home to 20% of the entire agricultural output of the united states. today, mike raises 1,500 head of cattle on his family farm. but small family farms are dying out on the high plains.

and mike callicrate has every reason to be worried. his family have seen the high plains die once before. for a time, the waves of migrants who settled in the high plains in the late 19th and early 20th centuries had enjoyed success. demand was high, and the crops were rich and plentiful. but deep ploughing and over exploitation had loosened the top soil. [wind blows tumble weed] and when drought came during the 1930s, followedy high winds, the fine soil of the prairies blew as far as chicago and washington d.c. the high plains became a dust bowl covering 100,000,000 acres of land.

many believed the day of judgment had arrived and the world was coming to an end. and in a sense, the worst environmental disaster in american history was a judgment. [haunting wind bellows] the farmers of the dust bowl knew there was water underground. they used to say they could feel it moving beneath their feet but they couldn't reach it. it was only in the '40s that geologists worked out that they were sitting on enough water to submerge the entire state of colorado, to a depth of 45 feet.

they called it the ogallala aquifer, one of the biggest underground reservoirs of fresh water in the world. the water contained between layers of clay, silt, sand and gravel has been there since the last ice age. and there was enough of it to fill lake huron. under the high plains, the ogallala reaches out for 175,000 square miles from the texas panhandle to south dakota. the wooden windmill pumps used by the early settlers made little impression on the massive reserves of water which lay underneath their farms. but after world war ii, they adopted better drilling technology and high-tech irrigation systems. soon, a new, industrial-scale agriculture,

was turning the lands of the dust bowl into america's breadbasket. but it all depended on the ogallala, and water was now being extracted from the aquifer faster than it could be replaced. by the 1950's, some of the survivors of the dust bowl we turning into millionaire landowners. it was boom time for america. the birth of rock and roll. nineteen cent hamburgers in the drive-in diner. modern life moving so fast that even a reservoir the size of lake huron couldn't keep up with the demand. almost a third of the ogallala's water has already gone, most of what's left will disappear in the space of a lifetime. the farmers of the high plains are looking down the barrel of a new dust bowl.

[mike] we are in yuma county and yuma county is probably the most irrigated county in colorado. the heart of the industrial agriculture of colorado. on the left is probably the biggest feed-lot in the country. there is about 130,000 in capacity there in that facility, and next to it on the west side is probably another 20,000 cattle. so right in that area, there could be as many as 150,000 head of cattle on feed. this is not a farm, this is a factory. so the big feed lot is going to be located where the water is and that is over the ogallala aquifer.

you can see all of the irrigation around. these feed lots, these are center pivots. the water used in a feed lot is not, is not what the cattle are drinking, it's what the crops are consuming in the production of the corn, the alfalfa hay. i can tell you that the industrial model will fail because it is not sustainable. it is like killing the goose that lays the golden egg. [chiwetel] the statistics stagger the imagination. more excrement comes from the biggest feed lot than a city the size of denver. the world's one-point-five billion cattle drink five times more water than the entire human race. [man 1] our bbq is prepared with just the right amount of heat to keep in the natural juices and hold in that wonderful flavor.

[chiwetel] over 90% of water from the ogallala is used for irrigation. [woman] ever hear of a criss-cross burger, it's easy to make and wonderfully good to eat. [chiwetel] it takes 600 gallons for a simple hamburger. [man 2] put the bbq'd meat on a tender bun and you've got some eating that is world-beating. try our famous barbeque at the refreshment stand now. [chiwetel] nearly a thousand gallons for a regular steak. [man 3] is there anything more important for a family meal than meat? better buy it from a store you can trust. [chiwetel] the water to produce a full-grown cow is enough for a ten minute shower every day for over 130 years. the ogallala will run out of water in the space of a lifetime. this is where it is going. it's not the water we drink which is the problem, it's the water we eat.

and the world's appetite is growing fast. there's been a 500% increase in meat production since 1961 and with the world population expected to grow to nine billion by 2050 further massive increases in production will be needed to meet demand. but by then, almost all the ogallala will be dry. [jay] whats become very clear is that the world's major aquifers are being depleted. some of them at a very rapid clip. weve got the aquifers in the arabian peninsula and across the middle east. turkey, syria, iraq, iran, india, bangladesh, north china plain.

over here in north western australia, really all over the world, so this is a cause for huge concern because those aquifers provide the water for irrigation to grow, uh, most of the food that we grow in the world. the high plains aquifer, in particular, we grow a tremendous amount of grain and, and beef. and this is a region that is projected to run out of groundwater in about 30 years. when i think about the collapse of water availability in our big food-producing regions, so much of that middle part of the united states is dominated by, by agriculture and provides food security for the country so what will those people do for jobs? and what will we do for food security? the implications for that i think are staggering. [digital bleeps from satellites]

[chiwetel] today, the face of the cattle business on the high plains is the face of industrial agriculture. they take the lion's share of the market. they take the lion's share of the ogallala's rapidly diminishing supply of water. the small farmers are being pushed aside. [mike] i think that we are in a really, really big mess as far as agriculture is concerned. that we would exploit our resources to the point where there isnt any more water. where there isnt any more healthy soils. what about my grandson? whats he going to do for water? [chiwetel] the threat to the ogallala's fresh water haunts the high plains. ghost towns are making a comeback.

tens of thousands of small farmers have sold up and moved on in the past 20 years, unable to keep pace with the demands of the market. [mike] what we would like to do up here is really show a regenerative model of production. what can heal the land? what can use less water? [chiwetel] from where mike's coming from, it's no surprise that he's become the champion of the traditional family farm. the dilemma is, the farms that use less water cannot satisfy the world's craving for beef. and the farms that produce most of the worlds beef are killing off the supply of fresh water for everyone. [mike] without the water of the ogallala aquifer the big corporations wouldn't be here at all. and the, and the thing that is so tragic, i think, is, is that the water is free. it doesn't cost them anything.

its absolutely free. it should be the property of people everywhere that live in the region. that water should be the people's water. like, it's like the air we breathe. i mean how long can you live without water? [chiwetel] but time on the high plains is running out. every day that passes, there's less water in the ogallala. when it's dry, it will take 6,000 years of rainfall to fill it up again. [mike] the corporate model of industrial agriculture is really a mining operation. it's really an extraction model of agriculture, where they use up the natural capital, that being water and soil. or when that water is depleted to a point that it makes no more sense to pump it, the big corporations and the industrial agriculture corporations

will be gone, and like in a mine, when a mine is spent, when a mine has no more gold, no more silver, no more coal, what does the mining company do? they shut the mine down and they leave. [poignant piano music plays] [mike] they leave behind broken communities. they leave behind empty feed lots and they leave behind the destruction. big industrial farmers are not going totop until the ogallala aquifer is pumping air. [digital bleeps pulse]

[digital bleeps fade] [percussive music builds] [chiwetel] brazil. the front line between nature and modern civilization. many believe that this is where the future of the world's climate will be decided. a frontier [gun clicks] where the idea of climate change ceases to be an abstraction. already, brazil is the world's ninth biggest economy. but economic development has come at a high price. the amazon is the biggest rainforest in the world.

but in brazil, legal logging has already reduced its size by almost a fifth. while the country's population doubled to over 200 million since 1970 the rainforest lost an area the size of texas. it is already possible to envisage an amazon without a rainforest. [speaking brazilian portuguese] there's mo fresh wat in brazil than anywhere on earth. but its biggest cities are being hit by drought. [crowd chants] water demonstrations in the streets, a sense that something in the climate is going wrong. and the owing awaress at the fatof the trees in the forest

and the failure of the rains in the city are somehow connected. [waves crashing] -[child screaming and yelling] -[waves crashing] [chiwetel] the man on the beach playing with his daughter is antonio nobre. [child shouting in brazilian portuguese] he wor for the brazilian institute for space research. and if you ask him what he does, sooner or later he will tell you the same story he tells his daughter: hes trying to save the world. he'll tell you that saving the world is stressful. that hes already had four major heart operations.

he'll tell you he delayed having a family because he was so involved with his work in the amazon r ainforest. [converses in brazilian] [chiwetel] tonights story is about the minotaur. but the story he tells about the amazon is far more frightening. [speaking in brazilian] [chiwetel] professor nobre is one of brazil's leading scientists and has made it his mission to make the world understand the coming catastrophe [speaks brazilian] [chiwetel] the amazon:

seventeen times the size of the british isles. the largest treasure house of plants and animal species in the world and for many the closest place on earth to the garden of eden. thirteen hundred different kinds of birds live among its trees. three thousand species of fish swim in its rivers. compared to the forest's 55 million years of existence, human beings are mere newcomers. but now the newcomers are threatening to destroy the rainforest forever. [antonio] we're producing a desert in, in the most rich forest ecosystem in the world.

one species from ignorance is destroying the whole system. we are basically compromising the very web of life that sustains us, without which we don't have a chance. i have this incredible suffering from people not listening. the indians are more careful, and they are more respectful because they are a product of the forest. one of the traditional leaders of the yanomami told me that if you chop down the forest, the rain will stop, and there will be nothing to drink or eat.

and when i asked him, how they knew about this connection between the forest and the rain, he said, "our ancestors have always known how the rain was made." "they learnt it from the spirits of the forest." [chiwetel] without trees, there would be no water. the thought had occurred to christopher columbus when he first came to america. the trees in the forest are not there because of the rain. the rain is there because of the trees. it's the idea that has been at the heart of antonio nobre's work in the rainforest. we have a phenomenon that's so mundane. everybody say, "oh, a tree".

but they don't realize, we don't realize what is happening inside. we don't realize how complex, how incredibly evolved. it took 400 million years to get to this point. t he tree is an incredibly complex machine that is able to pump water deep from the water in the soil, and pump it against gravity and keep going and going and going, all the way to the leaves. and release that in the atmosphere like if it were a geyser, and you don't see it because it is vapor, it is invisible. and as it does it, it's like an irrigation system in reverse. [chiwetel] water vapor alone will not turn into rain unless it is seeded. in the amazon, the forest produces its own rain

by throwing out into the sky clouds of volatile organic compounds, which transform the vapor into raindrops. and the more rain the forest needs, the more particles the trees release into the atmosphere. [antonio] it's magical, in a sense. it's magical dust that sprinkles there into the atmosphere, which makes the rain to come down, pixie dust. and this was the explanation for it, the solution to the mystery. we finally, "elementary, my, my dear watson." [orchestral music plays] [chiwetel] its been called the river in the sky. every day, each of the forests 400 billion trees

sends 1,000 liters of water into the atmosphere. twenty billion tons. more water above the tree tops than flows from the river amazon itself. now all of this is threatened by interests that want to turn the forest into cattle ranches and soya beans. [satellite digital bleeps] satellites from nasas landsat program monitoring the rainforest. for 25 years, photographs from space have documented the deforestation. 6,800 acres of rainforest destroyed every day.

nearly 300 an hour. an area the size of almost three football pitches every minute. [helicopter whirling] it is the job of ibama, brazil's environmental police force, to protect the rainforest. but it's a dangerous business. in the amazon, the fight against climate change goes head-to-head with the fight to make money. brazil has become the most dangerous country in the world to be an environmentalist. [helicopter whirring] midsummer 2018. ibama are on a mission near concelvan, in northwestern mato grosso, at the heart of an area known as the arc of destruction.

[speaking brazilian portuguese] [chiwetel] they'd hoped for an element of surprise but here, as often happens, the loggers have been tipped-off. [speaking brazilian portuguese] [chiwetel] militia protect the ibama investigators from ambush. [speaking brazilian portuguese] [chiwetel] the timber yard has a license. but ibama suspects it's a front for illegal logging.

[speaking brazilian portuguese] [chiwetel] they are looking for contraband timber, extracted illegally from protected areas. [speaking brazilian portuguese] [chiwetel] the bosses are missing. little can be done but to book the low-grade workers who are left behind. to those who want to save the rainforest, ibama have always been the good guys. but the odds have turned heavily against them.