The Life and Environments Through Time (LET) program, funded by the National Science Foundation, supports research that advances understanding of the patterns and processes related to the origin and evolution of Earth’s climate, environments, life, and sedimentary record. The scope of the program spans molecular, local, regional, and global scales, focusing on research conducted from the Archean Eon through the Holocene epoch. The program encourages studies that enhance knowledge of Earth's historical transformations and address how life and environments have co-evolved over time.

Research supported by the program can help predict and prepare for future global changes and promote the maintenance and security of ecosystem services that are critical for human societies. Projects may focus on integrating diverse data sets, developing models, conducting field studies, or using innovative techniques to uncover new insights about Earth's past environments and life systems.

Eligible applicants include institutions of higher education, such as accredited two- and four-year U.S.-based colleges and universities, as well as non-profit, non-academic organizations, including independent museums, observatories, research laboratories, and professional societies that are directly engaged in educational or research activities. Proposals that involve international branch campuses of U.S. institutions must include clear justification for conducting project activities outside the U.S. and explain the benefits of doing so.

The LET program has an estimated total program funding of 14 million dollars. While no specific award ceiling or floor is mentioned, proposals are accepted on an ongoing basis, providing flexibility for researchers to submit applications at any time. Cost-sharing or matching funds are not required.

Applications must be prepared in accordance with National Science Foundation guidelines and submitted through Research.gov or Grants.gov. Detailed proposal requirements, including formatting, evaluation criteria, and submission instructions, can be found in NSF Publication 25-517. For technical assistance or questions, applicants can contact NSF grants support at grantsgovsupport@nsf.gov.