Dan from Squirrel Hill's Blog Obama tells Africans that contaminated water is a smaller problem than global warming While speaking in Johannesburg, South Africa, President Obama said that global warming was “the biggest challenge we have environmentally†and that it was worse than “dirty water, dirty air.â€However, according to the World Health Organization, while global warming kills 140,000 people each year, air pollution kills 3 million people per year.According to UNESCO, each year, contaminated water causes 4 billion cases of diarrhea, 120,000 cases of cholera, 300 million cases of malaria, 12 million cases of typhoid, 6 million cases of trachoma, 200...