As a result of human activities such as the burning of fossil fuels for energy and land-use changes such deforestation, the concentration of carbon dioxide in the atmosphere is now higher that it has been at any time over the last 800,000 years .
Dealing With Various Themes And Issues
As a result of human activities such as the burning of fossil fuels for energy and land-use changes such deforestation, the concentration of carbon dioxide in the atmosphere is now higher that it has been at any time over the last 800,000 years .