The central Transantarctic Mountains are a polar fastness of superlatives: highest summit of the entire Transantarctic Mountains, Mt. Kirkpatrick (14,856 feet); largest outlet glacier, Beardmore Glacier (>100 miles in length, average 12 miles width); and outlet glacier with greatest discharge, Byrd Glacier (~20 km3/yr). Setting off from the endpoint of my previous blog, we leave McMurdo Sound heading south across the Ross Ice Shelf. The first major landmark is Minna Bluff, a 25-mile long ridge of lava that originates at the foot of Mt. Discovery. Scott's and Shackleton's polar parties left caches of food at the end of Minna Bluff. From there the mountain front arcs back and south again. Crossing the mountains at the rear of this reentrant is Skelton Glacier, a relatively short and snow-covered outlet glacier that was the route to the plateau used by Sir Edmund Hillary and his New Zealand tractor train traversing to the South Pole during the International Geophysical Year, 1957-58.
Another 100 miles to the south we come to Byrd Glacier. The most spectacular approach is to fly in over the 12,000 foot crest of the Britannia Range, which flanks this massive outlet glacier on its northern side. As one soars over the flat top of the range a vast corridor of textured ice fills the view. With nary a bend in its 85-mile length, Byrd Glacier cuts a 15-mile wide swath straight across the mountains. Radio echo sounding done in the late 1970's showed that the glacial trough beneath Byrd Glacier is a mile deep, comparable to the depth of the Grand Canyon.
South of Byrd Glacier, the Churchill Mountains rise from the ice shelf through a system of ridgelines and spurs to a crestline with peaks in excess of 10,000 feet. This rampart runs for 100 miles then splays into three, low-relief ranges before terminating at Nimrod Glacier, the next of the outlet glaciers. Unlike Byrd Glacier, with its straight path from the plateau to the ice shelf, Nimrod Glacier bends and twists through a curving course, in its central portion dropping more than 6,000 feet in a distance of 20 miles and producing some of the most savagely crevassed ice in the Transantarctic Mountains.
The mouth of Nimrod Glacier was the endpoint of Scott's 1902-03 party in their attempt to reach the South Pole. From there Scott, Wilson and Shackleton gazed south across the glacier to a spectacular massif, rising to an elevation of 14,042 feet through an intricate system of ridgelines that converge on its lofty summit. Named by Scott for Sir Clements Markham, the god-father of the expedition, Mt. Markham commands an incredible panorama to the north toward Nimrod Glacier and the country beyond.
100 miles south of Nimrod Glacier one comes to the Queen Alexandra Range with the highest elevations in the Transantarctic Mountains. The main massifs in the range, such as Mt. Kirkpatrick and Mt. Elizabeth, are generally blocky and flat-topped, owing to the horizontal, sedimentary rocks of which they are composed.
Beyond the Queen Alexandra Range is Beardmore Glacier, the route from the ice shelf to the polar plateau discovered by Shackleton in 1908-09, and followed by Scott's party in 1911-12 during their fateful race to the South Pole with Roald Amundsen. The medial portion of Beardmore Glacier is severely crevassed, but the western margin, which the explorers chose for their route, is relatively smooth and snow covered.
Beyond Beardmore Glacier are the Queen Maud Mountains, the fourth and final region to be covered in this series. This remote area includes the most scenic portion of the entire Transantarctic Mountains and the outcrop of the southernmost rock on the planet.