Answer:using fertilizers on crops
Explanation:carbon dioxide in the atmosphere is absorbed by plants.plants use it to produce their food. An increase in atmospheric carbon dioxide is caused by cutting down of forest and burning of fossil fuels.this increase in the emissions of carbon dioxide is harmful to the earth. Gases like chlorofluorocarbons ,carbon dioxide etc can cause global warming. This gases causes the heat not to escape from the earth atmosphere,just as it is in a green house. When this happens heat is trapped in the earth it causes global warming. These gases are released by burning of fuel, CFCs from old refrigerators and air conditioner.
Increase in the heat in the earth can cause melting of ice in the polar region.this can lead to a raise in sea level and flooding.
