Growing human population and the factories -greenhouse effect.
Greenhouse gases are considered as one of the main reasons behind global warming on our planet earth. The poisonous gases emitted by the industries, vehicles and other medium are increasing the rate of global warming. When these type of emissions are controlled, then the global warming is bound to reduce. It has been scientifically proved that on days when vehicles are less on the roads or on days when industries are closed, the greenhouse gases are emitted less and this results in lesser amount of pollution. This in turn definitely helps to reduce global warming