A leap second will be applied to Coordinated Universal Time on Dec. 31, 2016.

The decision to add a leap second is made by the International Earth Rotation and Reference Systems Service, an international standards body, to accommodate for variations in the Earth’s rotational speed. The U.S. federal government’s Global Positioning System (GPS) broadcasts leap second correction information in the navigation message. However, it is the responsibility of users to assure that their hardware and software recognizes and manages the leap second correctly; errors and equipment failures can occur when GPS receivers and clocks process the leap second signal incorrectly. Please ensure all software and firmware is up to date.

To be fully prepared, please read the “Best Practices for Leap Second Event Occurring on Dec. 31, 2016” document, sponsored by the DHS’s National Cybersecurity and Communications Integration Center in coordination with the U.S. Naval Observatory, National Institute of Standards and Technology, the Coast Guard Navigation Center, and the National Coordination Office for Space-Based Positioning, Navigation and Timing.

This blog is not a replacement or substitute for the formal posting of regulations and updates or existing processes for receiving formal feedback of the same. Links provided on this blog will direct the reader to official source documents, such as the Federal Register, Homeport and the Code of Federal Regulations. These documents remain the official source for regulatory information published by the Coast Guard.