A New Perspective on Water Poverty and Sustainability: Green and Blue Water Options to Attain the MDGs
Johan Rockström, Executive Director, Stockholm Environment Institute

Roberta Balstad: Thank you very much.

Our next speaker is Johann Rockström who is associate professor in natural resource management at Stockholm University. He is also executive director of the Stockholm Environment Institute, also known as SEI. He has been conducting research and development work for the past dozen years in developing countries, and has more than forty scientific publications in the area of water resource management, agricultural development, environmental management, systems research, and importantly for our topics today resilience. He is coordinator of several national and regional research development projects links to the Global Water Partnership, the Global Dialogue of Water for Food and Environmental Security, and the Resilience Alliance. Johann Rockström.

Johann Rockström: Thank you. I'll be introducing a new freshwater paradigm, which may contribute to untie the daunting Gordian knot facing humankind of how to secure sustainable freshwater to eradicate hunger and poverty. This may seem like an absolutely impossible task over twenty minutes, but I can comfort you that the task is essentially a question of shifting perspectives from looking at our home as a blue planet to instead looking at it in a perspective of a green planet. And let's see how we get there.

Now it will build quite a lot on what was presented yesterday by Frank Rijsberman and Ismail Serageldin, so we've seen a lot of the daunting challenges. I'd just like to point out the issue of growing social and ecological vulnerabilities, that we have a tendency, which was pointed out by Tim Palmer, of an amplitude of an increased frequency of environmental shocks, and that disasters hit vulnerable communities hardest.

Now this is a very disturbing correlation. On top you see the map of the hotspot of malnourished from the Millennium Development Project, but look at the graph below which is the distribution of semi-arid and dry sub-humid [?] savannas in the world, which show a very disturbing correlation between water scarce regions where current climatic variability is very high with the areas of malnourishment in the world. So the challenge of hunger is essentially a challenge of water management. And this is at the core of how to achieve the hunger and malnourishment challenges in the Millennium Development Goals.

So, food production consumes huge amounts of water. Serageldin pointed that out yesterday. 1,300 cubic meters per person per year to generate an adequate diet of 3,000 kilocalories per year. That's 90% of our human water requirements. A lunch consumes roughly four tons of water, and that is why water is in essence a water resource challenge for food.

Now, to be able to understand this the question is how can we tackle the challenge? Now this was pointed out earlier today, the very, very rapid increase in water withdrawals for particularly agriculture. As you see over the last 100 years we've essentially sixfolded water use. Agriculture is normally pointed out as a large consumer of water, the world's largest, 70%, but this I will argue is a very narrow and actually a flawed way of looking upon the freshwater challenge in the world. Now the reason for that is in the following. What we do today in water resource planning and management is that we do not look at the catchment as a whole, we focus on what we will call the blue water flow, which is the liquid water in our rivers and groundwater, and we omit the challenges and opportunities that lie in the upstream areas of river basins. We take the runoff generated from the upstream areas as a static constant, while acknowledging that 70% of the poor in the world

Now to be to tackle this we introduce a new freshwater paradigm, which is a paradigm of looking at the hydrological cycle from a green and blue water perspective. So rainfall falls on land and is partitioned in two fluxes. One flow is the return flow the atmosphere's vapor, which constitutes evaporation and transporation, that's what we call green water flow. It has a productive portion, transporation, which is taken up by roots, and gone back in the productive process of photosynthesis. Evaporation is non-productive. Soil moisture is a green water resource. Blue water resource, which is the focus of all water policy and management today, is what leaves the catchment in rivers, in aquifers, and finally reaches to ocean through large river systems.

Now if you look at the world you see quite an astonishing opening when you look at the hydrological cycle from a green and blue perspective. At the upper left-hand corner you see the global water cycle, with 60% of green water flow while runoff, blue water, is 40%. Look at India, for example, quite representative for the world with a 60-40 partitioning, green water flows generating essentially all ecological ecosystems services in terrestrial biomes, I'll come back to that, and blue water flow is what in the end supports irrigation. This is what we normally consider to be the major user of water, but it's a very small portion if you take a green-blue water perspective. But look at Kenya, for example, a country which is at the core of the Millennium Development Goals. Well, the major resource here is vapor, but we never count on it, it's never part of water resource planning. The statistics of water is down here. This is what we call 100% of freshwater, but in reality of course the Kenyan farmer deals with rainfall. So here lies an opportunity. This is not news. Already Levovic [?] in 1979 in his seminal work on global freshwater made the conclusion that soil moisture, which is actually 80,000 cubic kilometers of water which resides in the soil, and which is the core of all biomass production in the world, is of course a major, major resource. It's just that we don't see it by the eye.

Now what are the implications of our flawed biased picture from the past? Well here you have the classic type of water resource maps where you see water scarcity very abundantly around the world, with 30% of world population facing water scarcity by 2025. But how do you produce these maps? Well, you have the water resource, which is considered to be the blue water resource, the stable runoff resource, divided by growing water demands. Well what is water demand? Well water demand is essentially water for food. Now to be able to do that calculation rightly showing red countries here facing physical water scarcity by 2030, you of course have to assume that all the food is produced is blue water. Do we produce in the world with blue water, with water taken out from the rivers in irrigation systems? Well of course irrigation is important, but reality is that that's a very small portion of total food production. Green countries here are countries that for 80% or more depend on vapor fluxes in rain fed agriculture to produce their food. The world is essentially green. The blue countries here, as you see, correspond not surprisingly with the red countries in the upper corner. When you compare apples with apples it comes out right. But for all the other countries in the world you're comparing apples, blue water resource, with pears, green water producing the food. So this is of course a great frustration because it means that we have no clue whatsoever of how much water is actually used in the world to produce food for mankind, but the beauty is it opens up a whole new area of freshwater for management.

So, we know that we're facing a huge challenge in terms of the MDGs. Gordon Conway introduced the concept of a green-green revolution. We can not do what was done in Asia in the ‘60s, we now also have to take environmental sustainability into consideration, together with Malin Falkenmark in a book we produced quite recently we said it's actually a triply green revolution. It has to produce twice as much food over one generation, the first green, it has to be environmentally sustainable, but it also has to build essentially on upgrading rain fed agriculture in the world, where the small holder farmers are and 70% of the poor. But do we have the freshwater to achieve it? That's the big question.

Now, to be able to answer this question we have to look at the driving forces. And one of them, which I won't spend much time at all, which is climate change and the climate change induced changes, but that has been eloquently covered, just to say that one of the recent advances of course in ecology is our understanding of resilience, the need also to invest in making the precautionary principle operational, that we can not just see ecosystems as linear and predictable, they are complex and dynamic, leading to feedbacks, which means that we also have to have a buffered capacity to be able to absorb shocks which are very prevalent in the savanna zone in the world.

Now, to be able to illustrate this I'd like to just make the connection, which becomes quite complex, but you'll follow me here, our focus is livelihoods, our focus is to produce more food. In the upper corner here you see the on farm water balance. This is a very disturbing graph, but it's an indicator of the health of the farming systems in poor countries. Only 10 to 15% of the rainfall is actually productive green water flow. 75 to 85% of the water leaves the farmer's field either as evaporation or as runoff. Now one consequence of this is land degradation. Another factor here to consider is that farmers are facing market uncertainties, and that Africa, upper right, is the country most subject to climate variability today, that's drought frequency. This is an uncertainty, a socioecological uncertainty today. Now on this you add climate change. In the lower hand corner predictions of increased drought frequency, three consecutive drought years, not occurring at all today, but increasing with a factor 30% in the future, according to some of the climate predictions, and also a worrying trend of declining rainfall, for example, in west Africa. When you combine these two of course you realize the major challenge we're facing.

Now, what are the needs and what are the options? And this is the very worrying conclusion when you connect the Millennium Development Goals with freshwater. This is in time freshwater requirements to produce food in the world. 2002 is the reference year. We are today consuming roughly 4,500 cubic kilometers per year to produce food, 1,800 is irrigation, the rest is rain fed. But look at the red chart there. 2,200 cubic kilometers of new freshwater just to halve hunger by 2015. That is more than the world's current irrigation water consumption. If you want to really achieve the goal by 2030, eradicating hunger, you up another 6,000 cubic kilometers per year. This is a major challenge today not even addressed in the millennium development process. But we have opportunities to address this increase. Dark green countries here are countries that would have to more than double freshwater use in agriculture to be able to achieve the Millennium Development Goals. That's a massive challenge and, as you see, concentrated again in the savanna zones of the world.

Now, where will the water come from? Well the blue option is all that promising. Here you have what Frank also showed yesterday the over-appropriation in certain river basins in the world. These are rivers running dry. Now we've tried to calculate the contribution to these 2,200, and even the most optimistic scenarios of irrigation expansion, which as you know are loaded today with social and ecological concerns, you can only see roughly 50% of the need contributed from irrigation. 85% will have to come from more consumptive use through investments in small scale farmers around the world, and it doesn't change over the next fifty years.

Now, the trick is can we do this without any tradeoffs, can it be done without affecting downstream use? Well, the answer is no. The millennium ecosystem assessment made a massive effort and contributed to the world our understanding of the importance of ecosystem services. Just some key points here. Food production is key. Women are large losers if ecosystems are degraded. Vulnerable people stand to lose. And they point out the savanna zone, but they did not connect to freshwater. Now we have done that. And what you come out with then is a very simple conceptual framework. Here is your blue water. We've called direct use the direct economic use of water. All water policy today is focused up here, domestic use, irrigation, industry. That's the 70% I showed you in the beginning. Now indirect blue flows have received increased attention over the last decades. That is the environmental water flows to sustain aquatic habitats. Now we introduce the green domain, the direct use, green water vapor to sustain soil moisture sustaining forests, biomass, grazing lands, rain fed culture, economic sectors recently not considered at all as being freshwater consumers, and then the indirect use to sustain biodiversity, water sustaining biodiversity in ecosystems.

Now if you take this paradigm and try to calculate around the world how much water is used to sustain all biomes of the world, you have to start on the blue domain. Now here you have the answer why we consider facing a blue water crisis. We have 40,000 cubic kilometers of runoff, some of that is storm flow, some of that needs to be safeguarded for navigation and environmental flow, a portion of that needs to be used to flush salts in irrigation schemes. We have an estimate of roughly 5,250 cubic kilometers of available runoff, sustainable available. We're using 4,000. So it's true, we are facing a blue water crisis, we can not take much more.

But look at a global assessment, rainfall in the left, green flows, blue flows, and look at what happens when you try to attribute green water flows to sustain all systems in the world. If we are serious about sustaining woodlands, grasslands, grazing lands, arid lands, green water is doing a job, vapor is sustaining ecosystem services today. Same with blue water flows. The trick is that look at irrigation down here, a very small portion, rain fed agriculture up here. Water is doing a job, so we're talking about tradeoffs.

Just to give you the perspective that's the dot of all water policy focused today. This is the indirect blue, this is the direct green sustaining our forests, grazing lands, rain fed agriculture, and this is the rest sustaining ecosystem services. Of course this is a different perspective policy picture than the conventional view. Now if you take this down on the operational scale and you talked again to the Kenyan Ministry for Water Resources, Agriculture and Environment, of course this changes. Here you have the Kenyan ecosystems from savannas to forests, grazing lands. Here you have the green flow to sustain in. Savannas are the biggest consumptive use. Here you have irrigation. This of course changes the planning horizon. And we've tried to address this in terms of tradeoffs. And what happens is that if you really want to achieve the MDGs in India, for example, the blue water option will eat into unappropriated flows, but look at the green flow. If you really mean something about halving hunger you'll have to eat into other ecosystems consuming green water. There will be tradeoffs and that's the crisis of how to balance water for food and nature. And you can do those analyses across countries.

But can we do it, can we actually increase green water flow in this pace? So now I'll take you down to the farmer's field and we have to do it in a more productive way, we have to increase crop per drop as well. Now, this is the reality on the savanna. You often talk of savannas as dry lands, but actually there's ample water but at the wrong time. And we have a major yield gap, and this is a strange situation here, is Africa, for example, with the one ton agriculture farmers' fields extremely low, very high yields potentially achievable, India, Vietnam, Thailand showing the same thing. And here is just an effort to try and convince you that there is a potential to increase yields very substantially. Here is the portion of rainfall that is available in the soil, here is the portion of the water in the soil that actually takes a green path. Today only half goes into the soil and only half goes productively, leaving us at one ton per hectare. You can go up to four tons if you just get the water down in the soil and get it productively back to the atmosphere. We can double and triple yields.

Now how can that be done? Well the trick is to increase the capacity of water in the soil and to make the water available for uptake. Now I'll give you a couple of examples. One major development is conservation tillage, abandoning the plow and moving into minimum reduced tillage systems which enables the soil to absorb water and to produce more food. And here are examples from sub-Saharan Africa with major yield increases just by moving away from plowing into minimum tillage systems, getting more green water into the soil. Fertility is an issue. Here is rainfall against yield. Well, if you have your fertility right there's a linear relationship between rainfall and yield. If you don't have your fertility right it doesn't matter how much rainfall, your yield doesn't increase.

The interesting thing with conservation agriculture is actually that it appears to be most effective when your rainy season is poor, meaning that it is a drought-proofing technology. When it's really bad your yields increase with 100 to 150, up to 200%. Supplemental irrigation, a key issue in savanna regions. And here we have plenty of examples of appropriate small scale ponds collecting blue water, supplementing maize yields. This is from Kenya, also from Burkina Faso, major increasing yields particularly when combining it with soil fertility, bridging dry spells as a key to success. Subsurface tanks, technologies from China, tested out in Africa for supplemental irrigation.

Here is something that has never been tested before, and we hope to do that soon, of combining conservation agriculture with ecological sanitation to apply nutrients on soils from organic sources, closing the loops with food production with supplemental irrigation. These are kind of synergies that we haven't even explored yet.

Now, of course a base of perspective is required. We still could see increases of consumptive use here affecting downstream, but of course taking a base of perspective may give us the opportunity of at least targeting what has not been done before, the upstream poor communities.

And then finally, before some concluding remarks, showing something which is really exciting, when linking the social dimension with the crop per drop dimension. Now, this might appear like a complex graph but actually it just shows the cubic meters of water required per ton, and here is yield. Now look at what happens when the African farmer, which is producing down here at one ton per hectare, is roughly consuming 4,000 cubic meters per ton of freshwater. The reason why it's so huge is that such a large portion of the green water flow is actually evaporation. Now if you're able to double that yield level from 1 to 2 tons, which is a very small step, you're actually moving that farmer from 4,000 to 2,000 cubic meters per ton, a major reduction in water. You can actually produce more food with less water, and that's very, very encouraging. And you can only do it at the low yield range, because once you're up here where the American and European farmers are, evaporation is any more a large portion of the water balance. So we can bend the curve. We can actually achieve the Millennium Development Goals with progressively less water, but we still need major investments, but we can actually make a contribution through crop per drop.

This can be taken into governance, into management. We have a number of planning tools for integrated water resource management. We have together with International Water Management Institute launched an initiative we call the green and blue initiative to introduce these operational aspects into river basin, catchment, and community level management. We're very proud also to hopefully be able to contribute into the millennium village effort to be able to introduce these aspects into policy, planning and implementation.

So, ladies and gentlemen, just a couple of concluding remarks. The conventional blue water biased approach, the blue planet, is not adequate for the challenges we're facing. There's very little ground for the conventional claims of a global freshwater crisis. Instead there is a crisis, but it has a different face. One, the limited options to expand blue water flows, if we are serious about sustaining aquatic habitats. And two, the large risks for tradeoffs between water for food and water to sustain particular biomes in terrestrial ecosystems, biodiversity in our forests, savannas, grasslands. Savanna regions is the global hotspot if we are really zooming in on the Millennium Development Goals. They are not all that dry after all, there's six, seven, eight hundred millimeters of rainfall. The trick is to deal with the variability today, and increase in variability tomorrow. Now less than a triple green revolution is required, major risks of tradeoffs. There are now agrihydrological limitations to double, triple, often even quadruple yield levels even in the water scarce savannas. There's ample evidence from local innovations indigenous nearly driven often that this can be done. It is possible to produce more crop per drop, particularly among the low yielding farmers in the world. They are the opportunity to reduce water use for every increase in productive use. And governance has to change from a blue water biased IMM [?] approach that we're applying today to a green-blue water based integrated land water management resource scheme. And then just finally, implications for policy are significant. You have to move the freshwater policy away from being only a water resource ministry issue into ministries of agriculture and environmental policy. Human capacities need to be built urgently, supporting Joel Cohen's point on education.

Can the MDGs on hunger be met? Well, I think most likely yes. There's plenty of bright spots out there that show that yes, you can actually achieve a sustainable green revolution. But what are the legal implications when suddenly, if we really are serious about rain being water, so who owns it?

Thank you.