 These gases are usually broken down relatively quickly through environmental processes like photosynthesis; however, in recent years, studies have shown their atmospheric composition is increasing.Some studies believe this is a natural part of the earth's cycle while others claim it is due to the growing amount of fossil fuel emissions and the gradual deforestation of oxygen producing plants.The theory suggests that these changes in temperature, could affect the way ice and snow forms over the earth's crust, initiating a glacial shifting process, possibly created a rise in sea level from 0.5 meters to 1.5 meters.