Earth Overshoot Day marks the date when humanity’s demand for ecological resources and services in a given year exceeds what Earth can regenerate in that year. To determine the date of Earth Overshoot Day, Global Footprint Network calculates the number of days that Earth’s biocapacity can provide for humanity’s consumption, using the latest data, as explained on this page. The methodology relies on the latest edition of the National Footprint and Biocapacity Accounts, using additional data to overcome the unavoidably “time gap” in United Nations’ reporting procedures.
To address this “gap” and determine Earth Overshoot Day for the current year, Global Footprint Network establishes trendlines from the National Footprint and Biocapacity Accounts data and extends those trendlines to the present year. Where possible, more recent data (Global Carbon Project, International Energy Agency (IEA), etc.) are incorporated to strengthen the assessment for the “gap” years. The downloadable research report documents these datasets and methodology.
Based on these calculations, every year on June 5, World Environment Day, Global Footprint Network announce the date for Earth Overshoot Day of the running year. On June 5 2023, Global Footprint Network announced that Earth Overshoot Day 2023 would fall on August 2.