CO2 in atmosphere is a cumulative value since volume of a gas (ppmv) is an extensive property of matter. Area is the proper representation of a cumulative value, instead of a line. The area under the blue curve is compared to the area under the orange curve, the entire orange area.
It is worth mentioning that the blue area is fossil fuel and cement CO2 emission only. That is, the human CO2 which is absorbed in the environment has not been deducted from the human emission. Whereas, the orange area is CO2 emission minus CO2 absorption, or net emission. The net amount of human-produced CO2 from fossil fuels and cement is too small to be detected. The signal of human-produced CO2 in net global CO2 concentration is not detectable by statistical tools used by skilled statistical data analysts nor by climate scientists. Not only is the signal too small to be quantified, it is too small to be detected as a reproducible signal. The signal of fossil fuels CO2 emission is too small to be distinguished from random variations in the 100 times larger CO2 signal of natural CO2 concentration.
Carbon neutrality (aka net zero) and carbon pricing and carbon taxes are frauds. The theories of anthropogenic or human-caused global warming (AGW) and catastrophic anthropogenic global warming (CAGW) and human-CO2 caused climate change are not plausible science. Since the amount of human-produced-CO2 is too small to force a detectable change in net global CO2 concentration, then human-produced-CO2 cannot cause global warming or climate change.
CO2 emitted by humans is offset continuously by an equivalent amount of CO2 absorbed by the environment. The rate of natural CO2 emission and natural CO2 absorption are both more than 10 times larger per year than the rate of human CO2 emission. The amount of human emission is easily absorbed. Human CO2 emission is continuously mixed with CO2 reservoirs in both atmosphere and ocean surface and each of those reservoirs are about 100 times larger than annual human emission. The relative percentage of CO2 in the atmosphere which was emitted by humans (the so-called atmospheric fraction) is irrelevant nonsense; the environment is not selecting one CO2 molecule versus another CO2 molecule in any significant amount. The concentrations of CO2 in air and in ocean surface are independent of the source of the CO2. An amount of CO2 equal to the amount of CO2 produced by humans is absorbed by the environment. The source of the CO2 (whether human, biosphere, ocean) is not a variable in the phase-state equilibrium equation that determines atmospheric CO2 concentration at a given temperature of ocean surface or land surface. In other words, humans cannot change the net global average CO2 concentration nor the rate of change of CO2 concentration by controlling CO2 emissions from fossil fuels or cows.
On the other hand, humans could implement catastrophic planetary climate engineering and eugenics decisions, for example producing artificial clouds or population reduction programs, or taxing carbon footprints and limiting use of fossil fuel energy. Such foolish actions needlessly keep millions of people in poverty and could make earth uninhabitable and uninhabited.
(1) NOAA ESRL and Scripps Institution of Oceanography (SIO). http://www.esrl.noaa.gov/gmd/ccgg/trends/ and scrippsco2.ucsd.edu “The carbon dioxide data on Mauna Loa constitute the longest record of direct measurements of CO2 in the atmosphere. They were started by C. David Keeling of the Scripps Institution of Oceanography in March of 1958 at a facility of the National Oceanic and Atmospheric Administration [Keeling, 1976]. NOAA started its own CO2 measurements in May of 1974, and they have run in parallel with those made by Scripps since then [Thoning, 1989].”
(2) Boden, T.A., G. Marland, and R.J. Andres. 2017. Global, Regional, and National Fossil-Fuel CO2 Emissions. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tenn., U.S.A. doi 10.3334/CDIAC/00001_V2017
(3) Salby, Murry L. Physics of the Atmosphere and Climate. 2nd Edition. Date Published: January 2012. isbn: 9780521767187. https://www.cambridge.org/us/academic/subjects/earth-and-environmental-science/atmospheric-science-and-meteorology/physics-atmosphere-and-climate-2nd-edition?format=HB&isbn=9780521767187 http://www.cambridge.org/9780521767187
“Equally significant are transfers of carbon into and out of the ocean. Of order 100 GtC/yr, they exceed those into and out of land. Together, emission from ocean and land sources (∼150 GtC/yr) is two orders of magnitude greater than CO2 emission from combustion of fossil fuel. These natural sources are offset by natural sinks, of comparable strength. However, because they are so much stronger, even a minor imbalance between natural sources and sinks can overshadow the anthropogenic component of CO2 emission.”
“At an absorption rate of 100 GtC/yr, the ocean will absorb the atmospheric store of CO2 of 1000 GtC in about a decade. That absorption of CO2, which is concentrated in cold SST [Sea Surface Temperature] at polar latitudes, is nearly offset by emission of CO2 from warm SST at tropical latitudes. Warming of SST (by any mechanism) will increase the outgassing of CO2 while reducing its absorption. Owing to the magnitude of transfers with the ocean, even a minor increase of SST can lead to increased emission of CO2 that rivals other sources.” (3) Salby, p546.