The greenhouse effect is related to the increase in the average surface temperature which is considered "global warming". Global warming is the result of an increase in gases like methane, carbon dioxide, and other factors that lead to a rise in the planet's temperature.
The climate found in Nice, France is mediterranean, with hot and dry summers and rainy winters. The oceanic climatic influences are also felt.
Photosyntasis Releases Oxygen Not Carbon
Therefore The Answer
