glacial mass

Question 1

glacial mass balance

Answer 1

the balance between the inputs and outputs and year to year change in the ice budget - ablation vs accumulation

Question 2

inputs

Answer 2

snow - increasingly compacted over years turns from low density white crystals to high density clear glacial ice
avalanche from mountains ides
wind deposition

Question 3

outputs

Answer 3

-main output is water from melting
-where ice front extends over water, huge chunks break off, forming ice bergs (calving)
-evaporation and sublimation

Question 4

energy

Answer 4

glaciers mass + force of gravity generates potential energy and as glacier moves, movement is converted to KE which lets glaciers erode, transport, and deposit

Question 5

stores

Answer 5

-main ones are snow and ice
-seasonal variations in size of stores, specifically temperate regions
-flows and transfers of energy and material

Question 6

flows

Answer 6

evaporation, sublimation, meltawter flow, processes of glcial movement (internal deformation and basal slip)
-flows and energy transfers are more pronounced in warmer environments
-flows are where the material is moving in the glacier, from one store to another

Question 7

what is the glacial system

Answer 7

an open system with interactions from other systems such as atmosphere, ocean, and rivers

Question 8

neg feedback loop

Answer 8

regulation and reduction of a natural process

Question 9

pos feedback loop

Answer 9

enhance and speed up processes, promoting rapid change

Question 10

ablation

Answer 10

net loss of ice during a year - outputs exceed inputs = mass decreases and retreats = neg mass balance

Question 11

greenland ice sheet (pos feedback loop)

Answer 11

-ice absorbs 2% more solar energy per decade
-summer near surface temps in greenland increased at rate of around 0.74 degrees per decade
-predicted that ice surface reflectivity or albedo will drop by 10 % by end of decade
- stuck in feedback loop as winnowing of ice, worsened by soot blown onto ice from wildfires - increased temps so more melting, reducing albedo
-if warm enough to remove all snow, dakr impurities spread across surface and so more heat absomrbent environment ) dust and soot that were entombed for years)
-13.4% drop in min ice extent per decade on avg since 1980’s and more than half of ice sheet experienced melting in 2015 summer

Question 12

why feedback loops important

Answer 12

-help us understand why they’re disappearing so fast
-very difficult to reverse this feedback loop