This chart, from a geophysical study published in the journal of the National Academy of Sciences last year at about this time, shows carbon emissions by each recent human generation.
Generations before us have not hugely altered the atmosphere, but we’re changing all that.
Take a look at how much bigger our contribution to the problem has been than our parents, our grand-parents, and earlier ancestors, and what it will be like for our children if we don’t stop.
The solid lines show what happens to the level of CO2 with a business as usual scenario. The dashed lines show what happens when we come to our senses and reduce emissions to zero.
Here’s the full caption for the chart from the study:
"Fig. 4. CO2-induced warming commitments linked to each human generation since 1900. Only CO2 has been considered. The range between the dotted and dashed lines for each color illustrates the large range in realized temperatures caused by the effect of CO2 emitted by each generation in the past along with the present (2000–2025) generation.
Note, for example, the very large differences in estimated warming in 2100 depending on whether constant emissions are continued through the 21st century compared to zero emissions after 2025 (black lines).
If the current (2000–2025) generation emits carbon dioxide at the same rate as the previous generation and cuts emissions abruptly to zero in 2025, the calculated atmospheric CO2 in 2025 reaches 437 ppm and only drops to 382 (approximately the current level in 2005) by 2100.
It is worth recalling that constant emissions will lead to a linear increase in atmospheric CO2, not to stabilization. Atmospheric CO2 stabilization can be reached only with an emission scenario that eventually drops to zero."