Climate Change Facts - Human Impacts

  • There are an estimated 25-30 million climate refugees. Numbers may increase to 200 million, or up to 1 billion, by 2050.
  • Nepal’s first “climate refugee village” of 150 people is being resettled due to climate change-induced water shortage. (July 2010)


  • The US intelligence community considers global warming as a serious security threat. Top US intelligence analyst Thomas Fingar indicated that floods and droughts will soon cause mass migrations and unrest in many parts of the world. (2010)
  • Evidence points to global warming as a primary cause of the violence in Darfur. (Atlantic Monthly, 2007)


  • Warmer temperatures are causing the spread of malaria, Bluetongue virus, West Nile virus, dengue fever, and other diseases to reach millions more people never before exposed to them, in higher latitudes or on new continents.
  • An additional 400 million people could be exposed to malaria by 2080 due to climate change. (UN)
  • More respiratory diseases (like asthma) and mental illnesses (related to disasters) are expected with global warming.


  • Climate change disasters are already responsible for some 315,000 deaths a year, with another 325 million people severely affected. (Global Humanitarian Forum , 2009)

  • Half the world’s population will face serious food shortages within the century. (University of Washington researchers, in Science, 2009)   
  • Harvests already distressed by drought or floods in Russia, Germany, Canada, Argentina, Australia, Ukraine, Pakistan, etc. (Sept 2010)
  • Food prices rose 5% globally in August 2010. In Mozambique, food riots in response to raised bread prices led to 10 fatalities and 300 injuries. (Sept 2010)
  • High food prices that sparked deadly 2008 food riots worldwide were due to a combination of climate change and increased demand for animal feed from populations in India and China. (UN World Food Program)
  • The number of people suffering from hunger exceeded 1 billion for the first time in 2009.
  • Over 9 million people die worldwide each year because of hunger and malnutrition. Five million are children.


  • The world's rivers are in a “crisis state” on a global scale. Water supplies for nearly 80% of the world’s populations are highly threatened. Nearly a third of sources studied are also highly jeopardized by biodiversity loss. (US researchers Professor Peter McIntyre of the University of Wisconsin-Madison and City College of New York modeler Charles Vörösmarty)
  • Recent regional reports on water shortage:
    • The Middle East’s water supply has shrunk to a quarter of its 1960 level. (Arab Forum for Environment and Development (AFED), 2010) The Tigris and Euphrates rivers dropped to less than a third of their normal levels due to drought. (UN Inter-Agency Information and Analysis Unit (IAU))
    • UK’s increasingly hotter, drier summers could cause extreme water shortages as river flows are reduced by 80%. (Britain’s Government Office for Science, 2010)
  • Sources of groundwater for wells, which support half our world’s population, are running dry. (Lance Endersbee, Monasy University, Australia)  
  • 1.1 billion people lack access to safe drinking water. (World Health Organization, 2005)

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