Polar-class icebreaker
The vessels conduct Arctic and Antarctic research and are the primary icebreakers that clear the channel into McMurdo Station for supply ships.[5][6][7] In November 2013 four senators proposed an amendment to the 2014 Defense Appropriations Act authorizing the construction of four new Polar-class vessels, at a cost of $850 million each.[8][9][10] The four senators sponsoring the amendment were Maria Cantwell and Patty Murray, from Washington, and Mark Begich and Lisa Murkowski, from Alaska.On February 22, 2017, the U.S Coast Guard announced it had awarded five fixed-price contracts worth $20 million for the future heavy polar icebreaker design studies and analysis.On May 18, 2017, Adm. Paul Zukunft said that due to changes in the Arctic, the Coast Guard may have to increase the number of the future icebreakers, and the future icebreakers may have a requirement for space, weight, and power reserved for offensive and defensive weaponry which may include an anti-ship missile package.