Global mean atmospheric concentrations of carbon dioxide (CO2) (yellow and red), methane (CH4) (aqua and navy), and nitrous oxide (N2O) (light and dark blue), based on data from ice cores (dots) and direct atmospheric measurements from the Cape Grim Observatory, Australia (yellow, aqua and light blue lines) and from the Canadian greenhouse gas monitoring site at Alert, Nunavut (red, navy and dark blue lines).
Source
Climate Research Division, Environment and Climate Change Canada.
