A Dry Future For Our Planet

A Dry Future For Our Planet

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      gioietta kuo
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      A DRY FUTURE FOR OUR PLANET
      GIOIETTA KUO
      Oct 2012

      There is no doubt that water is the most essential element of life.   Yet  in many ways we use water profligately,  as if it is an infinite resource.  It is time we realize that water is the most precious resource which underpins everything we need for living.   It is important to realize that many of the phenomena described below, like the depletion of aquifers, consequent land subsidence, global desertification, loss of water due to ice melts,  sea level rise and change in precipitation pattern due to climate change are all irreversible processes leading to the loss of the precious resource.The world is  squeezed on either side of  water loss:  On the one side, thanks to climate change with rise in global temperature, we are witnessing for ever accelerating melting of glaciers depriving us of fresh water for  agriculture, drinking and other uses.  In addition there is also the massive melting of ice caps like Greenland and Antarctica.  All this melting goes to raise sea level with eventual  devastating consequences of flooding to our major cities and land areas.  This brings into question how long we shall be able to continue to feed our rivers with water from mountain glaciers like that of Himalayas or Andes and how many years  will it be when our important coastal cities will be flooded.  On the other side of the water loss, the world is truly wasting what water we have from rivers, lakes and aquifers  on a colossal scale. According to UN, more than 80% of our used water is neither collected or treated[1], as we use and dispose of water from  these sources as if the flow will never cease.In this paper, we shall examine both aspects of water resource –  how we are losing water through ice melts and how we waste the precious water we have.  We discuss the phenomena, the causes and what  we might do to mitigate and adapt if we want to avoid an extreme global water scarcity.

      I.  WATER LOSS THROUGH ICE MELTS
      The paper by Thompson and Kuo[2] which will appear in the wfs.org  conference book 2012 entitled “Climate change: the evidence and our options” documents 30 years of ice core data -records of climatic and environmental variations from the polar regions and low latitude high elevation ice fields in 16 countries.  The ongoing widespread melting of high elevation glaciers and ice caps,  particularly in the middle and low latitudes, provide some of the strongest evidence that a large scale pervasive and in some cases rapid changes in Earth’s climate system is underway.  Here  we are not dealing with computer modeling, though most climatologist today believe that the present climate change is  due to anthropogenic human forces,  rather we are presenting data  for over last 8000 years showing that the present CO2 and methane concentrations are something unlike anything  the conditions the ice fields were accumulated and sustained before.  In addition there is 160 years  of record of direct temperature measurements to substantiate the exceptional  melting of the last 2 decades.  

      a.  Sea Level Rise
      About  half of the rise in sea level is due to thermal expansion.  As for the rest oceans are rising because ice is melting.   So far, most of this water comes from mountain glaciers and ice caps.   If Greenland ice sheet were to melt completely the sea level would rise by 7 meters,  West Antarctica by 5 meters and East Antarctica by  50 meters.   If the Earth were to lose just 8% of its ice,  the consequences would be dire – Cities like New York, London and Shanghai would be submerged.  Countries like Netherlands, Maldives and Indonesia are already  struggling with inundation and demographic problems.  The lack of fresh water  for drinking and agriculture is already effecting billions of people in the dry season in countries like India, Nepal, Vietnam, South China which depend on the rivers fed by the shrinking Himalayan glaciers.Over most of 20th century , sea level rise rose about 2 mm per year, but since the last 2 decades, it has been 3 mm per year.

      b. Effects Of Climate Change
      Climatologists and glaciologist are most alarmed, not just because ice is melting, but the accelerating speed of the melt over the last 2 decades due of course to the sharp rise in the Earth’s temperature. Since 1980s, the global temperature rise has been 0.16 deg C per decade as compared to 0.06 deg C per decade before. As we know the hottest years on record have been the  latest decades.  For example, the rate of ice melt in the Himalayas  in this century is twice the rate of 4 decades before.  From 1963-1978, the rate of ice loss on Quelccaya glacier in Peru was about 6 meters/year, but from 1991-2006, it averaged a horrendous 60 meters/year.    Our climate system is a highly complex one with many feedback loops which means a small change in one of many parameters can in principle trigger a large environmental change.   Climatologist call this a ‘tipping point’ when we might be suddenly faced with an abrupt and devastating change in our climate, so violent from which we cannot recover.  This is a very stark warning that we cannot ignore.

      c.  Mitigation And Predictions
      So what can we do to preserve fresh water from ice melt and ultimate sea level rise which can bring devastating consequences?  Obviously, society should limit further rise in the Earth’s temperature. We all know the basic fixes required such as replace fossil fuel by renewable sources for electricity generation, reduce deforestation and so on.  But what is not universally realized is we must change our lifestyle with emphasis on conservation and efficiency starting with the housing sector, mass transport, local food production and more [3].The IPCC predictions for global temperature rise to the end of 21st century are 1.1- 2.9 deg C for their lowest emission scenarios and 2.4- 6.4 deg C for their highest.   Most of the public seem to accept that there will be a 4 deg C rise by the end of this century.   I do not accept this prediction because I do not think IPCC’s 6 scenarios can faithfully predict CO2, methane  emission and other parameters for the next 90 years.   Rather, I would accept a prediction up to 2030, where most climatologists would  agree on a figure of 1.5 deg C from 1900.    What does this mean for future ice loss?   Since we have seen that the phenomena are highly non linear,  it is impossible to forecast.   All we can say is we should adapt measures to reduce Earth’s temperature rise as urgently as we can. 

      GLOBAL WATER USE
      Every 3 years UN convenes a World Water Forum with  35,000 high level representatives from 180 countries to report on the current world water situation.  Demand for water is expected to increase by 55 % over the next 4 decades, according to the Water Reform Challenge from the Organization for Economic Co-Operation and Development (OECD).  They point out global rapid urbanization, altering global economy, rising temperatures and most of all the fact that by 2050, there will be more than 40% of the world population – 3.9 billion –  likely to be living in river areas in the grip of severe ‘water stress’ [1].  Already in developing countries there is a tremendous economic and human cost to the water crisis – 1.1 billion people live without clean drinking water and 2.6 billion lack adequate sanitation [4].  Since 1900, more than 11 million people have died because of drought, and more than 2 billion have been affected by it.  The OECD is advocating urgent reform in terms of taxation, tariffs and transfer to encourage greater water efficiency[1].   But the fundamental fact which we cannot not ignore is we are adding 2 billion more people on Earth by 2050,  mostly in developing countries where there is endemic poverty.

      a.  Climate Change Bringing Drought
      There no doubt that our climate has changed over the last decade bringing a different rainfall pattern which exacerbates the existing water scarcity [1]. Warming at the equator drives a climate system called Hadley Cell [2].   Warm moist air rises from the equator, loses its moisture through rainfall, move north and south and then dry air falls to around 30 degrees latitude creating desert and arid regions.  This brings more persistent drought in Australia, the Mediterranean, American Southwest and Africa. 

      World Desertification
      Desertification [5] is devouring more than 20,000 square miles of land worldwide every year – affecting 74% of the land in North America, and Africa.  About 14 million square miles  of the world’s 20 million square miles  of useful dry land for agriculture has suffered erosion and soil degradation in more than 100 countries.  One billion of world’s population is affected by desertification, forcing people to leave their farms and increase the trend of seeking jobs in cities.  Though climate change may trigger the desert process, much of it may be caused by humans in over-cultivation, exhausting the soil.  Over grazing of livestock strips the land of grass.  Most prominent of all  deforestation removes the trees which allow the topsoil to be blown away.  Deserts are like hungry monsters, advancing and encroaching on cities.   For example [6], the Gobi desert is moving south at 3 km/year and sand dunes are forming just 70 km from Beijing causing frequent blinding sand storms on the city. Despite massive spending by the Chinese government on land reclamation and replanting, China cannot keep up with the rapid expansion of the desert. Only 7% of Chinese land is viable farmland, and half of China’s 617 largest cities face water deficits.  This is  perhaps the biggest national threat and it has impending grave consequences. According to a UN study [5], about 30% of Earth’s land – including the 70 % of dryland is affected by drought, causing 33,000 people to starve to death every day. 

      Use Of Aquifers
      An aquifer [7] [8] is an underground layer of water- bearing permeable rock or unconsolidated materials like gravel, sand or silt from which fresh ground water can be extracted  with a well.  It is one of the most precious water resources.  Because we cannot see the extent of a given aquifer, there is a tendency to pump until the well runs dry.  At this point, the aquifer is mostly not replenishable and the reduced water pressure in the compressible rock or gravel causes it to subside  under the weight of overlying geologic materials.  Ground subsidence due to excessive over pumping is visible in many parts of the world.  In China [9], 50 cities are threatened by land subsidence, especially in the Delta region of the Yangtze river and the North China Plain causing enormous economic damage to the infrastructure.  In some industrialized countries, water from aquifers are used freely for recreation such as building a golf course in the middle of a desert in Nevada. Although the proportion of water used is small,  nevertheless we should be aware that we are using a precious resource that is not for free.

      Drinking Water Security.
      Humans need 3 liters of water for drinking per day.   Total household use amounts to 15% of our water. Due to increasing urbanization, we spend globally $100 billion on bottled water.  This  is undesirable because of the use of energy for transport and bottling and it is more economical to use filtered tap water. However, under drought conditions, desalination both with fossil fuel or nuclear reactors are being considered, such as already practiced in Australia [10].  However, this comes at a cost: both in heavy investments in plants and production electricity requirements.

      Water For Agriculture.
      Although global rising temperature may lead to increased precipitation, the pattern and distribution of the hydrological cycle has changed and this creates uncertainty in farming.  There is no doubt that agriculture is already shifting to higher  latitudes  such as Canada due to rise in global temperature and lack of water in subtropical regions.  A study by IRRI [11] has derived a rule of thumb from crop ecologists that for every one degree C above the norm  the yield of wheat and rice and corn fall by 10%.About 66-80% of our water go into agriculture, as it take 3000 liters of water to produce food for one person per day.   Current methods of irrigation for rice  based on alternate wetting and  drying of soils  have proved to produce high yields.  New methods like  hydrological modeling have been used for detecting groundwater salination.  Food should be produced locally so as to reduce transport costs. Changing to a more vegetarian diet reduces water usage  as it takes 2,000-16,000 liters of water to produce one kg of beef while one kg of wheat needs only 800-4,000 liters.   The use of greenhouses for market gardening with new irrigation methods of aeroponics, hydroponics and drip irrigation save water and have many advantages over outdoor farming where much water is lost to runoffs.

      III CONCLUSION.   

      WATER STRESS
      We list here the major causes of water stress Population growth.  Adding 2 billion people in the next 40 years increases severe scarcity for water.
      Climate change. 
      Accelerating  global temperature rise leads to ice loss from glaciers and ice caps.  This is an irretrievable process. Change in weather pattern affects our agriculture. Rapid urbanization.  Trend toward urbanization is accelerating,   Already 60% of China live in cities.   In European cities, ground water is being used  at a faster rate than it can be replenished, thereby increasing demand on both supply and sanitation.

      Depletion of aquifers.
      Many cities in the world, as well as irrigation for agriculture, are using this resource at an unsustainable rate.  It is important to realize that this process is irreversible.  Once the aquifers run dry and land subsidence has occurred this resource is depleted.World desertification is an irreversible process. Land  lost is irretrievable. Expansion of business activity.  Increasing demand of water in industrialization. Water pollution and protection.  One of the main concerns in the world today. Many pollutants threaten our water supplies but the main reason is the discharge of sewage into natural waters in developing countries.

      Water and conflict.  
      Many rivers cross national frontiers.  Many predict future wars will be over water. 

      OUR FIRST PRIORITIES

      Already there are a billion hungry people in the world [12] .  This just underscores the importance of water.  What can we do to reduce hunger in the underdeveloped world?  Where ever possible we should stop the processes which lead to irrecoverable water stress.  Doubtless, the first action the world should tackle is the collection and treatment of the 15% of water  for household uses as this becomes increasing relevant with rapid urbanization.  This applies not only to major cities like Beijing but also those like New York in industrialized countries.  However, a radical investment in infrastructure is required.  In addition electricity power is required for recycling.   There is a trade off:  so long as 65% of world’s energy comes from fossil fuel, we will inevitably add to Earth’s rise in temperature leading to more water loss through ice melts.  

      REFERENCES 
      “A hard, dry future for the planet”  http://   http://www.indepentent.co.uk/environment/nature/a-hard-dry-fu… 
      “Climate change: the evidence and our options”  Thompson and Kuo,Conference book, July 2012  wfs.org 
      “Energy in 2030 and conservation”  World Future Society,        wfs.org,  World Future Review Fall  2011  Vol 3 No 3 
      “Water crisis” http://www.worldwatercouncil.org/index.php?id=25 
      “Deserts and Desertification”   http://didyouknow.org/deserts/
      “The desertification of the Gobi desert and its effect on Beijing” http://www.geo.utexas.edu/courses/371c/…/Welker_Desertification.pdf “Aquifer” http://en.wikipedia.org/wiki/Aquifer 
      “Aquifers” http://ga.water.usgs.gov/edu/earthgwaquifer.html9. 
      “Urbanization and land subsidence in China.  http://www.iaeg.info/iaeg2006/PAPERS/IAEG_031.PDF10. 
      Ocean in the Bottle | Allianz Knowledge  knowledge.allianz.com/…/mitigation_adaptation/?…/australia-        water…i…11.  International Rice Research Institute, IEEI     http://www.earth-policy.org/books/pb3/PB3ch3_ss3 
      “Almost a billion go hungry worldwide”, Sarah Morrison, The independent. August 5 2012 http://www.independent.co.uk/news/world/politics/almost-a-bill…

      Gioietta Kuo, from Cambridge, Oxford and Princeton, is a research physicist specializing in energy problems.  She has published  over 100 articles in World Future Society, wfs.org, amcips.org and other worldwide think tanks.  As well as in ‘ People’s Daily’ and ‘World Environment’ , Magazine of the Chinese Ministry of Environmental  Protection, and others in China. She can be reached at

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