during the first four decades of the present century and since 1940, a period of general temperature warming, the glaciers have all receded. Ice fronts have retreated up to 5 km from positions reached in 1862 and ice levels have dropped over 100 m.
Paleogeographic evidence for the high valleys of New Guinea suggests that four advances and retreats of ice can be inferred within the period of probable human settlement. - (DWG)