On 10.07.2019 we made the following observations at the Unteraar glacier:
Dead ice mass in front of glacier
From the once impressive dead ice mass in front of the Unteraar glacier only two small pieces remain.
The two pieces of ice left over from the big dead ice mass are on 10.7.2019.
The western part is larger and still max. 3m high and already interspersed with various cracks and fissures. This enlarges the surface accessible for the warm air and accelerates the melting.
Western piece of the dead ice mass in front of the Unteraar glacier on 10.7.2019.
Fissure in the western rest of the dead ice mass on 10.7.2019.
Below the western part a 70cm high cavity/tunnel has formed, which crosses the ice from east to west.
Cavity under the western rest of the dead ice mass on 10.7.2019.
On 10 July 2019, the meltwater from Unteraar glacier flowed mainly through four glacial streams.
At the southern edge of the glacier tongue a lot of water flowed out of the glacier at the foot of an ice wall. This outflow already existed in summer and autumn 2018. It is astonishing that no actual glacier gate has formed here so far. A similar outflow existed at Oberaargletscher a few years ago.
Show before/after photo comparison of location 3 at Unteraar Glacier.
Approximately 50m further northwest, a small glacier gate flowed considerably more water than in autumn 2018. As the ice above the glacier gate is not very thick, this glacier gate is expected to shift rapidly to the west.
Middle glacier gate on 10.7.2019.
Little melt water flowed out of the area of the collapse structure.
See also comparison of location 4
The glacier gate on the northern side of the glacier tongue has shifted further to the west due to the melting of the front and has increased its span. Compared to the summer of 2017, only little meltwater flows out of this glacier gate. There is probably a more or less direct connection to the collapse structure.
Northern glacier gate on 10.7.2019.
Our observations since summer 2017 show how quickly the drainage of a glacier can change. In addition, large runoff volumes shape the glacier forefield and the deposited sediments create the areas and conditions that pioneer plants need to thrive.
Snow situation
The snow conditions on the Unteraar glacier were similar to those of the last few years. So we didn't have to cross a single snow field.
