ppm

A file-based API for historical atmospheric CO₂ concentrations.

The API returns mean, de-seasonalized trend data from NOAA Trends in Atmospheric Carbon Dioxide, which includes monthly and annual data ranging from January 1979 to today (always a few months behind). Recent months for which there are no estimates are approximated from NOAA's daily estimates.

How to use

The API is hosted on GitHub Pages and makes the following endpoints available:

Globally averaged marine surface annual mean data

https://philippschmitt.github.io/ppm/v1/{YYYY}

$ curl https://philippschmitt.github.io/ppm/v1/1998/
{
	"year": 1998, 
	"ppm": 365.7
}

NOAA data does not include the annual mean for the current year (obviously...). For the current year, the API returns the mean of the monthly trend data available-to-date.

Globally averaged marine surface monthly trend data (de-seasonalized)

https://philippschmitt.github.io/ppm/v1/{YYYY}/{m}

$ curl https://philippschmitt.github.io/ppm/v1/2022/1/
{
	"year": 2022, 
	"month": 1, 
	"ppm": 416.13
}

NOAA data is a few months behind (three, at time of writing). Missing months are filled in with data from the Estimated Global Trend daily values dataset. Each month uses the first available row, i.e. first day of the month.