VICKSBURG, Miss. (Feb. 11, 2018) --When the "polar vortex" dipped down into the United States more than a week ago -- leaving the Midwest and other parts of the country in a painful deep freeze -- an Arctic expert at the U.S. Army Engineer Research and Development Center's Cold Regions Research and Engineering Laboratory knew why.Dr. Martin Jeffries, research physical scientist, has studied the Arctic for over 40 years. Before arriving at CRREL, he was an Arctic Science Advisor and Program Officer for Arctic and Global Prediction at the Office of Naval Research for seven years. During this period, Jeffries was detailed to the White House Office of Science and Technology Policy for 25 months.Jeffries was hand-picked by the Corps after serving in these prestigious positions to augment in size and scope the Corps' Arctic and cold regions science and engineering research activity at CRREL so that its status as the Nation's resource for Arctic expertise is further cemented. To accomplish this goal, he's working with CRREL's cold regions experts to develop, for example, strategic research plans on topics such as sea ice and permafrost.He became interested in the Arctic while taking an undergraduate class in glaciers and landscape at the University of Sheffield, in the United Kingdom. "I found the subject fascinating and the professor was inspiring," he said. "When I was working on my master's degree at the University of Manchester, also in the United Kingdom, I had my first opportunity to experience the Arctic of northern Norway."Jeffries recently served as one of three editors of the "Artic Report Card 2018," an annual update -- published since 2006 and issued last December -- on the state of the rapidly changing Arctic environmental system. "The Arctic is changing because it's warming at twice the rate as the rest of the world," Jeffries said.Highlights of the ARC were widely reported by several federal agencies, such as the U.S. National Park Service, and through numerous media outlets, including CNN and National Public Radio."The ARC, which is an interagency effort led by the National Oceanic and Atmospheric Administration, addresses everything from physical science topics like air temperature and terrestrial snow cover to biological science subjects, such as caribou and reindeer," Jeffries said. "The Arctic Monitoring and Assessment Programme in Norway, a working group of the Arctic Council, sends this publication out for a blind peer review, which lends credibility and authoritativeness to the effort."Jeffries described why the Corps and the Army are concerned about what happens in the Arctic. "The Arctic is an integral part of the Earth's system; it isn't a cold, dark distant region that exists separate or isolated from the rest of the world," he said. "The U.S. is an Arctic nation -- Alaska is America's Arctic. The Army and Air Force have a considerable military presence there, protecting the northern flank of the U.S.""There is much to protect: in addition to a population of almost three quarters of a million people, there are the Bering Sea fishery, North Slope oil and other natural resources such as minerals, forests and natural gas. Changes are now taking place in snow cover, permafrost and vegetation that are critical to armed forces activities; these changes will impact infrastructure, such as roads, runways and pipelines, and will accelerate coastal erosion."Offshore, summer sea ice retreat is opening the Arctic Ocean, leading to growing interest in the Arctic and its natural resources by Arctic and non-Arctic nations. Retreating sea ice cover is leading to a longer open water season, raising the prospect of an increase in maritime shipping and calls to build a deep water port in a place where the U.S. currently has none," he said.Changes taking place in the Arctic impact everyday life in the lower 48 states that comprise the U.S. mainland as well. "There is a growing body of evidence that the warming of the Arctic is affecting lower latitudes," Jeffries said. "The polar vortex events, for example, are cold air outbreaks from the Arctic that affect the weather, and they're increasing in duration and severity.""The hypothesis is that a diminished temperature gradient between the Arctic and mid-latitude regions of the Earth is slowing the jet stream, which now favors a more meandering north-south path and shift to lower latitudes, bringing Arctic air to the 'lower 48' and elsewhere," he said. "That wavier jet stream extending into lower latitude regions is what the media has been calling the polar vortex."