it's been a while meaning, it's been a while definition | English Cobuild dictionary. been. 1 Been is the past participle of be. 2 verb If you have been to a place, you have gone to it or visited it. He's already been to Tunisia, and is to go on to Morocco and Mauritania...
Carbon dioxide is a by-product of respiration ] and combustion combustion: Combustion is the process of burning by fire. . Green plants remove carbon dioxide from the atmosphere by photosynthesis. Living organisms-including all plants and animals-release energy from their food using respiration.Respiration and combustion-burning-both release carbon dioxide into the atmosphere.These processes form a carbon cycle in which the proportion of carbon dioxide in the atmosphere remains about the same.The animation should help you to understand how the cycle works.espiration and combustion-burning-both release carbon dioxide into the atmosphere. These processes form a carbon cycle in which the proportion of carbon dioxide in the atmosphere remains about the same.
The burning of fossil fuels releases the carbon dioxide removed from the atmosphere hundreds of millions of years ago. Other carbon dioxide sources include volcanoes and bush fires. A: The single largest factor for increasing atmospheric CO2 is the burning of fossil fuel. Human beings release 30 billion tons of CO2 into the atmosphere each year from fossil sources. Over the decades this has lead to an increase from 280 parts per million to now over 390 ppm of CO2.