Ash Carter, President Barack Obama's new defense secretary, made his Pentagon debut on Tuesday.

Carter emerged from a black sport utility vehicle at a snowy, icy Potomac River entrance to the Pentagon. He made no comments to a gathering of reporters, photographers and cameramen. His wife, Stephanie, slipped and fell on the icy pavement. She laughed it off and officials indicated she was not injured.

Carter went ahead with most of his planned first-day schedule even though the federal government was closed due to inclement weather.

Carter, 60, is Obama's fourth secretary of defense. A formal swearing-in ceremony was scheduled at the White House later in the day. Carter replaces Chuck Hagel, who resigned under pressure.