Marine Debris Emergency Act of 2012

Marine Debris Emergency Act of 2012 - Amends the Marine Debris Research, Prevention, and Reduction Act to authorize the Administrator of the National Oceanic and Atmospheric Administration (NOAA) to declare a marine debris emergency upon determining that marine debris: (1) is an immediate threat to living marine resources, the marine environment, navigation safety, or public health of the United States; and (2) requires federal resources to supplement the state and local resources available to alleviate such threat.

Authorizes: (1) a governor of a state to request that the Administrator declare such an emergency in such state or a region that includes such state; and (2) the Administrator to request that the governor provide information on the nature and immediacy of the threat and the nature and amount of state and local resources that have been or will be committed to alleviating it. Directs the Administrator, within 30 days after receiving a governor's request, to either grant the request or explain why it was not granted.

Directs the Administrator: (1) in evaluating marine debris grant applications, to give preference to projects to address marine debris emergencies, including projects to address marine debris that has introduced or is likely to introduce marine invasive species into the United States; and (2) within 60 days after receipt of an application for such a grant, to approve or disapprove the application and to disperse funds to an approved grantee.

Directs the Administrator to take steps to encourage marine debris grant recipients to: (1) educate staff and volunteers who are engaged in marine debris response efforts on the potential threats that marine debris and marine invasive species may pose to the United States with respect to living marine resources, the marine environment, navigation, and public health; and (2) coordinate their response efforts with relevant federal, state, local, and nongovernmental entities.