Meade Glacier Rapid Retreat 1986-2014, Alaska

Meade Glacier drains the northwest portion of the Juneau Icefield, with meltwater entering the Katzehin River and then Chilkoot Inlet. The glacier begins in British Columbia and ends in Alaska. Here we use Landsat imagery to examine changes in the glacier from 1984 to 2014. The glacier experienced a slow continuous retreat from 1948 to 1986 of 400 m, the glacier ended on an outwash plain. From 1991-2006 JAXA’s EROC program noted a retreat of 570 m, retreating into a lake basin. In 2007 the lower 2.5 km of the glacier was stagnant and heavily crevasses, poised for collapse in a developing proglacial lake. The 1948 map of the glacier indicates no proglacial lake with the glacier terminating on an outwash plain.
meade map
USGS Topographic map from 1948 aerial photographs

In 1986 the terminus is indicated by an orange arrow, the 2014 terminus by a red arrow, two tributaries that connect to the Meade Glacier are indicated by yellow arrows and the snowline at is indicated by purple dots. The snowline is at 1250 m in 1986, there is no evident lake at the terminus of glacier just an expanding outwash plain. Both tributaries are 750 m+ wide where they join Meade Glacier. By 2004 a 400 m long proglacial lake has formed at the terminus. The two tributaries from the south at the yellow arrows no longer are connected to the glacier. The snowline is at 1450-1500 m, which is much higher than in 2004 on Taku Glacier or Brady Glacier. In 2009 the snowline is at 1400 m, the proglacial lake has expanded to 600 m in length. In 2014 the proglacial lake is 3.5 km long, the entire lower 2.5 km of the glacier has collapsed since 2007. There is still considerable relict ice floating in the lake. There is a substantial lake along the southern margin of the glacier where a tributary streams enters the main valley. This indicates the glacier will quickly retreat to this point by further collapse into the lake. The snowline in 2013 and 2014 was quite high and the summer’s quite warm which aided in the lake expansion. The snowline in 2014 is at 1400 m on Aug. 2, the date of the imagery, the high snowlines ensure continued mass loss and glacier retreat. There was still six week of summer melting remaining on the date of the imagery. The Meade Glacier is poised to continue a rapid retreat in the near future its retreat parallels that of most Juneau Icefield glaciers including the next glaciers to the south Field Glacier and Gilkey Glacier.

meade glacier 1986
1986 Landsat image
meade 2004
2004 Landsat image
meade glacier 2009
2009 Landsat image

meade glacier 2014
2014 Landsat Image

Hoboe Glacier retreat, British Columbia

The Hoboe glacier is a distributary tongue of the Llewellyn Glacier draining the Juneau Icefied in Northwest Britsh Columbia. In 1984 I had the opportunity to hike the length of the glacier carrying supplies to the terminus for a master thesis research project of Richard Campbell at the Univ. of Idaho, during the JIRP summer field season. The glacier is 4 km long separating from the Llewellyn Glacier at 3800 feet and ending at approximately 3000 feet. This is our view from the glacier surface notice the evident trimline above the ice surface showing how thick the glacier used to be.This glacier has receded 2200 meters since early visitors to the area mapped its terminus around 1910, and 3900 m from its maximum advance of the Little Ice Age. The Google Earth views below are from 2001 images. The glacier has retreated 450-500 m in the fifty years that the Juneau Icefield Research Program has been examining it. The first view is looking up glacier and the next two looking down glacier. In all three a trimline is evident where vegetation has not had time to develop due to retreat of the last 75 years. The image above is an aerial photograph taken by Don McCully of JIRP. The trimline in the photograph is 75-85 meters above the glacier surface indicating the thinning that has occurred in the last century. Nearly one meter a year due to the recent climate change that has enhanced summer melting and reduced winter snowfall. The Hoboe Glacier is continuing its retreat like all but one of the nineteen outlet glaciers of the Juneau Icefield. Including the Gilkey Glacier and Tulsequah Glacier.