Documentation > Greenhouse effect > Acting collectively > Is leaving one's car in the garage sufficient to suppress the CO2 emissions in excess ?
In 1998, the first source of greenhouse gases in France was, and by far... agriculture (graph below).
There are two major reasons to this fact:
the first one is not specific to France: greenhouse gases are not restricted to CO2, and for the other gases (methane and nitrous protoxyde, mainly) agriculture is by far the first source.
the second one is specific to France, but also to other countries that share the same characteristic: electricity production, which generally comes first among the CO2 sources in developped countries, has only a tiny share in France because of nuclear energy (80% of electricity production) and hydroelectricity (15% of electricity production).
Hence if France had the same way to produce electricity than USA or Germany, the ranking of emissions would probably look something like the following graph
Anyway there are other conclusions that probably remain valid in other countries:
trucks emit "just" one third of what cars do,
households emit more through heating their homes than through driving,
and most of all they emit more through eating than through driving !!
This being said, we can play at looking at what a prolongation in 20 years of the trends observed from 1990 to 1998 gives (caution: a prolongation of trends is NOT a forecast).
Let's nevertheless note that a prolongation of trends is more or less legitimate depending on the activity or sector. In particular, the "liberalization" of the electricity sector might well lead to a partial substitution of nuclear energy by gas in power plants, what is not necessarily the best possible idea regarding greenhouse gases emissions, not mentionning the fact that gas is not a renewable energy.
If we leave apart the "electricity sector question mark" for France, the two major increases on the grounds of the prolongation of trends would come from:
cars (on the left)
trucks ("transportation services", before last on the right).
It is therefore perfectly justified to pursue "efforts" in the transportation sector, but one should not forget that succeeding in just this field would be far from enough if we want to efficiently mitigate greenhouse gases emissions.