
Use the Earth System Research Laboratory (ESRL) Global Monitoring Division site to find specific atmospheric data files. Navigate through the criteria to narrow your selection of data.
For example, click on Greenhouse Gases as your main category, and then choose Carbon Dioxide (CO2) or Ozone (O3) as the type of greenhouse gas. From there you select how the air sample was collected, such as air samples collected in glass flasks, and how frequently the samples were collected (e.g. monthly). Your results then display specific locations around the world that meet these requirements.
You can download data from 16 gathering sites scattered around the globe (displayed as 3 letter identification codes, including South Pole/Antarctica).
Note: These links go to pages that contain raw data. You need to copy and paste the data into Excel.