An official website of the United States government Here's how you know
A .gov website belongs to an official government organization in the United States.
A lock () or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
| October 10: | 423.57 ppm |
| October 09: | 423.56 ppm |
| October 08: | 423.55 ppm |
| October 07: | 423.55 ppm |
| October 06: | 423.54 ppm |
The figure shows daily averaged CO2 from four GML Atmospheric Baseline observatories; Barrow, Alaska (in blue), Mauna Loa, Hawaii (in red), American Samoa (in green), and South Pole, Antarctica (in yellow). The thick black lines represent the average of the smoothed seasonal curves and the smoothed, de-seasonalized curves for each of the records. These lines are a very good estimate of the global average levels of CO2. Details about how the smoothed seasonal cycle and trend are calculated from the daily data are available here.