What human-influenced environmental factor has the greatest impact on global warming?

Answer 1

Environmentally, the answer is probably deforestation. The great forests of the world, which used to remove thousands of tons of carbon dioxide from the atmosphere, have been cut down.

Answer 2

There are a lot of options and the order can be debated. They include:

• Deforestation
  
• GHG emissions (CO2 and methane)
  
• Depletion of the fish stocks
  
• Urbanization leading to heat islands
• Overpopulation