Human Impact on Earth’s Atmosphere Part.III

The legacy of mining is not only the hole in the ground and the pile of spoil left behind: it can affect air and water over great distances. The Ilo smelter in Peru emits 600,000 tons of Sulphur compounds each year, and cyanide in the waste affects marine life in a 20,000 hectare area. Small scale gold mining by hundreds of thousands of miners in the Amazon basin releases an estimated 100 tons of mercury into the river system each year.

As the world’s population expands past the six billion mark, it becomes more and more unevenly distributed. The great concentrations do not always occur on the most productive land; and people tend to gravitate towards what are often already large cities. In 1950 the largest metropolitan areas were all in the developed world- New York, London, Tokyo and Paris. Now those have been overtaken dramatically by Shanghai, Calcutta, Bombay and Singapore rising rapidly on the list. The developing world’s urban population now larger than the total population of Europe, North America and Japan combined.  Many of the cities have grown beyond the control of planners and include illegal slums that pack millions of people together and concentrate population and disease. An estimated 600 million people in the cities of the developing world lack clean water, sanitation and secure homes. Even if living standards improve, cities seem set to expand putting more land under concrete and producing more fumes from industry and vehicles in congested streets.