![](https://247wallst.com/wp-content/uploads/2022/08/imageForEntry21-iIK.jpg)
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2008
> Carbon dioxide (CO2): 384.98 ppm
> Methane (CH4): 1,789.94 ppm
> Nitrous oxide (N2O): 322.11 ppm
![](https://247wallst.com/wp-content/uploads/2022/08/imageForEntry22-yiu.jpg)
Source: mmac72 / iStock via Getty Images
2009
> Carbon dioxide (CO2): 386.42 ppm
> Methane (CH4): 1,793.63 ppm
> Nitrous oxide (N2O): 322.88 ppm
![](https://247wallst.com/wp-content/uploads/2022/08/imageForEntry23-a5e.jpg)
Source: olegkozyrev / iStock Editorial via Getty Images
2010
> Carbon dioxide (CO2): 388.71 ppm
> Methane (CH4): 1,796.84 ppm
> Nitrous oxide (N2O): 323.70 ppm
![](https://247wallst.com/wp-content/uploads/2021/12/imageForEntry22-sNi.jpg)
Source: jankovoy / iStock via Getty Images
2011
> Carbon dioxide (CO2): 390.57 ppm
> Methane (CH4): 1,803.42 ppm
> Nitrous oxide (N2O): 324.61 ppm
2012
> Carbon dioxide (CO2): 392.64 ppm
> Methane (CH4): 1,810.33 ppm
> Nitrous oxide (N2O): 325.58 ppm