Reasons for Global warming : 1. Release of carbon dioxide(co2) in to the atmosphete by power plants by burning the fossil fuels. 2. Release of carbon monoxide in to the atmosphere by burning gasoline by automobiles. 3. Methane emissions from animals agriculture. 4. Deforestation especially tropical forests gor wood,pulp and farm land. 5. Increase in usage of chemical fertilizers on crop lands. Current global warming trend is called AGW - Anthropogenic Global Warming ( which means caused by humans).
GReen houses gases are released into the atmosphere in many ways , including thoung the burning of fossil fuels like coal, petroleum & gases coming out from cars ,burning garbags,plyothens & people cutting trees (deforestation) and so on
Some enviroment warm for example arctic,tundra,ganga they also release czrdon that may have been stored for thousand (100) of years