Antarctica Case Study

What is the average thickness of the ice sheet?

Average ice sheet thickness is 1.6km 

How much precipitation does Antarctica receive each year?

<100mm of precipitation a year

What area is covered by ice in Antarctica?

13.8m km²

What is the average air temperature?

-60^o

Describe the wind speeds reached:

Wind speeds can reach 320km/hr, commonly 160km/hr 

How many lakes are there, and which is the largest?

379 lakes, the largest is Lake Vostok, 240km long 

Give some key facts about the ice sheets:

• 8.5% of the ice sheet volume is below sea level 

• The EAIS is largely covered by 1 dome  

• The WAIS is covered by 3 major domes 

• Max sea ice coverage is 1.6x10⁷ km² in September, increasing by ~1.7% per decade 

What are the primary functions of ice loss?

Largely occurs at the ice-ocean interface by calving or bottom melting on ice shelves 

Where is the greatest ice loss occurring?

• Average loss is 142 Gt/year

• Greatest loss is occurring on the western edge e.g. Pine Island and Thwaites glaciers

Describe ice flow in Antarctica:

• In the EAIS this is largely due to internal deformation 

• Local high flow areas are due to subglacial lakes, but they have little large-scale impact 

• In the WAIS ice streams dominate, e.g. Ross-type streams which are wide and 1km thick 

Describe the Larsen C ice shelf and it’s change:

• In 2017, 10% of the Larsen C shelf calved into the sea (the size of Luxembourg) 

• The shelf usually holds back an equivalent of 1cm of sea rise from the ice behind 

• The iceberg itself didn't cause a rise as it was already in the ocean