A Picture on Earth Day Plot of historical and possible future atmospheric CO2 concentration. Green: ice core data. Blue: direct atmospheric measurements at Mauna Loa observatory. Dark red dashed projection: future scenario, involving achievement of net zero greenhouse gas emissions by 2040, that would result in projected warming of about 1.5 °C by 2100. Purple dashed projection: future scenario, involving achievement of net zero greenhouse gas emissions by 2055, that would result in projected warming of about 2 °C by 2100. For the implications of achieving (or failing to achieve) these climate goals, see here. Inset: Earthrise, an iconic photograph of our Earth taken from lunar orbit by Apollo 8 astronauts just a little over a year before the first Earth Day. Subscribe to Blog via Email Enter your email address to subscribe to this blog and receive notifications of new posts by email. Email Address Subscribe Share this:Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window)MoreClick to share on WhatsApp (Opens in new window)Like this:Like Loading... Related