SG5: Glacial lake management at Lake Palcacocha

Question 1

What is Lake palcacocha?

Answer 1

A proglacial lake.

Question 2

Why has it formed?

Answer 2

Result of the retreating Palcaraju glacier plus water from precipitation and is dammed by moraine.

Question 3

What is there concerns about the lake?

Answer 3

The lake may flood the town if lake levels continue to rise.

Question 4

What is the human activity being taken place?

Answer 4

• 8m dam was completed in 1974 to help reinforce the terminal moraine.
• lake has been artificially lowered by 3m
• pipes that drain excess meltwater

Question 5

What are the reasons for this activity?

Answer 5

• There’s been a 3-5 degree increase since 1940s
• Increase in potential energy stored in the lake fear a glacial lake outburst flood (GLOF).
• Concerns that with the increased GPE the consequences would be more devastating as the water will travel with more speed
• The lake has flooded before in 1941, a chunk of glacier fell into the lake which created a wave for the displacement of the water creating a GLOF.
• In 2003 there was another GLOF, there was a landslide and part of the steep lateral moraine slid into the lake causing a 8m tsunami.

Question 6

What is the percentage decease for the GPE since managing the lake?

Answer 6

47%

Question 7

What is the effect on changing glacial landforms, the consequence of these changes on the landscape?

Answer 7

• Lake has become shallower and now never reaches 30m deep
• The volume of the lake has reduced from 17- 10 million metre squared
• The maintained level of water in the lake means there are less fluctuations in its size