We know that in order to curb climate change, we need to reduce our CO2 emissions. But what does a tonne of CO2 actually amount to?
In our daily activities, we emit a certain amount of CO2 through our actions, our travel, our work, the way we eat, the way we entertain ourselves, and the waste we produce.
Today, when we talk about the greenhouse gases that we emit, individually, by country or worldwide, we take the tonne of CO2 equivalent as the unit of reference.
So as not to remain in abstract notions, let us try to imagine what a tonne of CO2 emitted is.
Because CO2 has a cumulative effect in the atmosphere, it is the main gas responsible for global warming. The concentration of CO2 in the atmosphere today is similar to that of the Pliocene, a prehistoric period during which, 3 million years ago, temperatures were 3 to 4°C warmer and the oceans 15 to 20 metres higher. Trees were more numerous and grew in Antarctica. They had absorbed CO2 in very large quantities which they slowly stored in the soil. Today, especially with the melting of the ice, we are releasing these gigantic quantities of CO2. We have entered a vicious circle: the more CO2 we emit, the more it accelerates global warming and the more it releases.
We must therefore reduce ourcarbon dioxideemissions .
The mass of carbon dioxide (CO2), an invisible, colourless and odourless gas, is 1.964 g/litre or 1.964 kg/m3.
At ambient temperature (25°C) and sea level, this occupies a volume of about 535 m3. This is larger than the volume of a two-storey bus.
By the forest, of course! Forest ecosystems recycle carbon and as such play a major ecological role in the global balance. Throughout their lives, thanks to the biological mechanism of photosynthesis, trees capture the carbon dioxide present in the atmosphere. They store it in their trunks, branches, roots, leaves and in the biomass (in the litter and in the soil). Once the trees have been harvested, the CO2 trapped during their growth remains stored throughout the life of the products made from the wood.
A 7,000 km journey at the wheel of a recent small diesel car (emitting 100 to 120 g of CO2/km) is the equivalent of a round trip from Paris to Moscow by car.
By consuming 418 litres of petrol in a vehicle, i.e. about 8000 km with a small engine capacity
By making a Paris-New York return trip by plane
By spending 2.5 tons of paper, the equivalent of 15 Douglas fir of 90 meters
To produce around 12,000 kWh of electricity (knowing that the production of one kWh emits between 0.7 and 0.9 g of CO2, according to RTE). This is equivalent to the electricity consumption of a family of 4 for three years.
To make 8 computers
By four years of using an internet box
To produce 76 kg of beef, the equivalent of 507 burger
By using 500 m3 of gas or 380 liters of fuel oil to heat your home
5,800 km in a diesel SUV of 2,500 kg for an average consumption of 6.5 liters / 100 km, or 8 Paris-Marseille journeys by car
In order to respect the Paris Agreement concluded in 2015 following the COP21 to limit global warming to 1.5 ° C, we must now drastically reduce our CO2 emissions .
In 2016, a report by ADEME and the Ministry of Ecological Transition estimated that a French person emitted on average 11.9 tonnes of CO2 / year. However, it would be necessary to arrive at less than one tonne of CO2 per person and per year to meet the objective of reducing our greenhouse gas (GHG) emissions.
Since 1990, the reduction in GHG emissions has been around 15% in France.
Globally, we tend to emit less CO2, except in the transport and digital sector. Indeed, half of the data stored by companies in the world is obsolete or useless, emitting 6.4 million tons of CO2 in 2020 .
It is therefore very important to reduce our digital footprint , but also our CO2 emissions linked to transport, as well as our overall electricity consumption, knowing that the France's carbon impact is lower than that of its European neighbors thanks to its nuclear fleet. But nuclear energy poses other problems and, moreover, the share of nuclear energy is set to be reduced in France.
In 2010, to emit 1 tonne of CO2, it was necessary:
about two weeks to an American
a little over a month to a European
one year for an Indian
Let us be careful not to leave the bill for our emissions to poorer countries to settle.
Today, the European Union takes third place on the podium in terms of global CO2 emissions, behind the United States and China.