On December 4, 2017, I wrote a blog regarding Moody’s Investors Service’s threat to downgrade state and municipal credit ratings if they failed to adequately plan for and attempt to mitigate climate change risks. A day later, in conjunction with the North American Climate Summit, Chicago’s mayor and dozens of other mayors signed the “Chicago Climate Charter,” which calls on mayors to work to achieve a reduction in greenhouse gas emissions that’s equal to or more than that required by the 2015 Paris Agreement. The charter would require participating cities to track and publicly report greenhouse gas emissions and take action to plan for climate change related impacts in local infrastructure and energy planning. While these actions may not have been in direct reaction to Moody’s threat, such forward thinking may minimize the risk for participating cities in future rating downgrades relating to climate change impacts.