The principal cause is the combustion of fossil fuels (coal, natural gas and oil) and biomass to produce energy, get electricity, produce materials for transportation, etc. The industrial production (manufacturing and construction), through use fossil fuels get heat and steam for the various stages of production and  require large energy consumption, the electrical energy  supply, this  produces more than a quarter of the emission of greenhouse gases.

The growth of the population that makes a growth in the medellín extension, that which in turn increases the amount of vehicles from 478000 to 1'347.736 that we have today, since 2005.

 

Other important cause is the geological location of the valle de aburrá, that makes difficult the flow of winds, this problema is not a responsability of the people, is a natural cause.