Antarctica Flashcards
1
Q
West Antarctic ice sheet
A
- Rapid change
- Unstable
- Divided by transantarctic mountains
- 3000m above sea level
- Can be over 2000m thick
- Bed rock under is sloping
- Grounding like (floating ice) beneath thin ice
2
Q
East Antarctic ice sheet
A
- Largest ice sheet
- 2835m above sea level
- Mountain ranges above ice sheet
- 85 degrees
- Contributes to sea level rising 53m if it melted
3
Q
Transantarctic mountains
A
- Uplifted sedimentry rock
- Divide east and west Antarctica
- Streatch for 2000+ miles
- 4500+m
- Largest in Antarctica
4
Q
Antarctic peninsula
A
- 80% covered with ice
- 800mile northward extension of Antarctica
- Highest point 3184m
- 70km wide
- Peninsula Gustav ice shelf most northerly ice shelf
5
Q
Mass balance
A
- Surface mass balance: peninsula has highest accumulation rates 1000mm per year
- Total mass balance of 2000 giga tones per year
- Interior Antarctic ice sheet: dry and cold, less than 22mm per year
- Mass losses increasing —> West and Antarctic peninsula
- Mass balance in west Antarctica dominated by dynamic loss and gain from sea
6
Q
Changes across millennia
A
- Not always covered with ice
- Located near the south pole on Pangea
- Ice could not form, global temps 20 degrees hotter
- Co2 20 times more —> enhanced green house effect
7
Q
Change in Antarctica over 100 years and 50 years
A
100 years
- Overall mass has decreased (negative mass balance)
- Increase in global temps
- More outputs than inputs
50 years
- West coast of peninsula experiencing rapid warming, one of most warming parts of planet
- Southern ocean temps increase by 1 degree since 1955
8
Q
Changes in antarctica seasonaly
A
Summer
- Points to sun in summer all day long
- Sun does not set till winter, Antarctic day
- Temps do not exceed 0 except from coast
- Average mass balance negative
Winter
- Dark all day long, Antarctic night
- Sun may peek above horizon
- Average temp -34.4
- Average mass balance positive
9
Q
Climate change
A
- Rapid warming of oceans = under side of ice to melt
- Eventual collapse
- Rise in global sea levels
