There is as yet no machine-readable data file available that gives daily atmospheric CO₂ readings from any of the many monitoring stations around the globe. Until there is, this fills in.
It scrapes the manually-entered data out of Recent Daily Average Mauna Loa CO₂ that is maintained by the Earth System Research Laboratory (part of the US government’s National Oceanic & Atmospheric Administration). That data is added to a CSV file (of all recent readings) and a JSON file (of just the last valid reading, ignoring any NAs).
How to use it
git clone email@example.com:wdenton/noa2co2.git cd noa2co2/ bundle install
To run from crontab with RVM you need a special wrapper script (change the directory as needed):
30 5-12 * * * cd ~/noa2co2/; ./rvm_noa₂co₂.sh
Direct links to the data
GPL v3. See COPYING.