Respuesta :
Today in society many trees are being cut down which releases oxygen and since there are less trees more CO2 is kept in the air. The burn of fossil fuels also releases CO2 into the atmosphere as well.
Back in the day only volcanoes contributed to the increase of CO2 now things like deforestation increases CO2 because less CO2 can be taken in by plants also burning fossil fuels is another contribution to the increase of CO2
