Grinnell Glacier is located at 48.75356, -113.7313. In 2005 this glacier covered an area of 615454 m2 and in 1966 it covered an area of 1020009 m2 . That is a change of -39.70 % over this time period.
Most of the glacial research inside of Glacier National Park has concerned Grinnell Glacier. From the early part of the 20th century until today geologists have collected a tremendous amount of data in and around Grinnell. Early images show the absence of Upper Grinnell Lake due to the amount of ice and snow filling the bowl now filled with the runoff of this glacier. If you have hiked to a glacier in the Park it was most likely Grinnell as many visitors make the trek in to see this natural wonder. Most folks begin at the Many Glacier Area and hike the 5 miles in but we have never been to the glacier from the east side as the vantage point we were interested in was from high above. We made 2 treks into the Glacier and used the Highline trail for the first and the Loop Trail for the next. We saw all the ant-sized visitors enjoying their pilgrimage and basking in the sun on the shores of Upper Grinnell Lake from our perch on the side of Mt Gould.