The 2022 Earth Month theme is "Invest in our Planet." Being good stewards of the environment where Marines live, train and operate in is crucial for the long-term sustainability of our planet. Earth Month serves as an opportunity to educate others on the importance of being environmentally responsible and highlight DoD and Marine Corps initiatives, programs and partnerships that make our installations, infrastructure and systems more resilient. - The 2022 Earth Month theme is "Invest in our Planet." Being good stewards of the environment where Marines live, train and operate in is crucial for the long-term sustainability of our planet. Earth Month serves as an opportunity to educate others on the importance of being environmentally responsible and highlight DoD and Marine Corps initiatives, programs and partnerships that make our installations, infrastructure and systems more resilient.