A comprehensive inventory of maximum glacial extent in Glacier National Park during the peak of the Little Ice Age
Dates
Publication Date
2018-07-09
Time Period
2005
Time Period
2009-06
Time Period
2014-10-19
Time Period
2015-08-22
Time Period
2015-09-12
Time Period
2015-09-25
Acquisition
2016-06-12
Acquisition
2016-08-20
Acquisition
2016-08-21
Acquisition
2016-09-15
Acquisition
2017-09-29
Citation
Fagre, D.B., and Martin-Mikle, C.J., 2018, A comprehensive inventory of maximum glacial extent in
Glacier National Park during the peak of the Little Ice Age: U.S. Geological Survey data release,
https://doi.org/10.5066/P95YJ3CN.
Summary
This data release consists of digitized glacier margins that represent the maximum extent of glaciers in Glacier National Park (GNP) and two glaciers on U.S. Forest Service’s Flathead National Forest land during the peak of the Little Ice Age. Glacier margins are based on moraine deposits that result from active glaciation, and do not depict perennial snow and ice. Moraines are continuous arcuate rock deposits with distinct crests that form at the ice edge of active glaciers. The criteria used for identifying the former size and location of glaciers were a) the presence of a terminal moraine, b) the presence of one or both lateral moraines, and c) whether the identified glacier area was 0.020 km2 (five acres) or more. Previous work [...]
Summary
This data release consists of digitized glacier margins that represent the maximum extent of glaciers in Glacier National Park (GNP) and two glaciers on U.S. Forest Service’s Flathead National Forest land during the peak of the Little Ice Age. Glacier margins are based on moraine deposits that result from active glaciation, and do not depict perennial snow and ice. Moraines are continuous arcuate rock deposits with distinct crests that form at the ice edge of active glaciers. The criteria used for identifying the former size and location of glaciers were a) the presence of a terminal moraine, b) the presence of one or both lateral moraines, and c) whether the identified glacier area was 0.020 km2 (five acres) or more. Previous work also included hummocky morainal debris immediately in front of well-defined moraines. This release includes a comprehensive inventory of past and present glaciers in GNP as well as a subset of the 37 named glaciers. Final digitized glacier margins, based on moraines, were subjected to independent review by other scientists.
This dataset was created to develop a time series and history of glacier recession in Glacier National Park (GNP), Montana, USA. The dataset delineates the perimeters of glaciers of Glacier National Park and two additional glaciers on U.S. Forest Service’s Flathead National Forest land during the peak of the Little Ice Age (mid-nineteenth century). The peak of the Little Ice Age is the most recent maximum extent in glacier size for which there is still significant morainal evidence. Establishing the rates of glacier retreat, using the decreasing area of glacier ice, is key to understanding the Glacier National Park ecosystem and future state of resources. For instance, glacial meltwater is critical habitat for endangered stream insects. More broadly, retreating glaciers are indicative of long-term climate change and have hydrologic and ecologic importance to many park resources. Glaciers and their retreat are of great interest to park visitors and the American public and are part of Glacier National Park's appeal. This is important because Glacier National Park is a major driver of the regional economy. Appropriate use of these data include comparing Glacier National Park's glacier area from different periods, such as more recent years included in an earlier data release (Glacier margin time series [1966, 1998, 2005, 2015] of the named glaciers of Glacier National Park, MT, USA), and to different parts of the world. The change in glacier area can be used to create models of glacier-climate interactions, and to estimate glacier contributions to streamflow.
