The French government in a 21-page report on global climate change found that several factors have led to an increase in average global temperatures from 1975-2003.
The increase, the report said, was mainly due to rising levels of CO2 in the atmosphere, which the French government said was "unequivocally" linked to human activity.
"Solar activity, which has slightly decreased on average since 1975, cannot be dominant in the observed warming during this period," the report read.
The report added that rising CO2 levels are a threat to the climate and to oceans, which may see their chemistry altered because of the changing atmosphere. Melting sea ice, the report added, could have a detrimental impact on aquatic and land habitats.
The French report noted that climate change can only be assessed by long-term observations of the atmosphere.
The report was commissioned by French Minister of Higher Education and Research Valerie Pecresse.