Lecture 16 Arctic climate change

Question 1

As snow and ice melt … land and ocean surfaces absorb more solar energy

Answer 1

darker

Question 2

More trapped energy goes into .. than …

Answer 2

warming, evaporation

Question 3

Atmospheric layer that has to warm in order to warm surface is .. in arctic

Answer 3

shallower

Question 4

As sea ice retreats, .. .. absorbed by the oceans is more easily transferred to the atmosphere.

Answer 4

solar energy

Question 5

Alterations in … and .. circulation can increase warming

Answer 5

atmospheric, oceanic

Question 6

permafrost is ground that has been frozen consistently for at least .. years

Answer 6

2

Question 7

..% of land in the N.Hemisphere is permafrost

Answer 7

24

Question 8

permafrost stores carbon as .. and ..

totalling …Gt

Answer 8

peat, methane
1300 Gt
-more than twice atmosphere C

Question 9

…pg of C could be released from thawing permafrost by 2100

Answer 9

350

Question 10

arctic greening refers to more … plants expanding as a result of rising temperatures

Answer 10

productive

Question 11

greening tundra can result in increased C sequestration by … Pg C y-1

Answer 11

0. 20

- 7-20% of global annual land sink

Question 12

arctic sea ice is declining .. per decade

Answer 12

13%

-12 lowest sep ice extents in last 12 yrs

Question 13

1995-2005 global sea ice declines from .. million km2 to .. million km2

Answer 13

7, 3

Question 14

if global warming stays below 1.5c there’s a ….. chance of iceless arctic
if limited to 2c there’s a … chance

Answer 14

1/100,000,

1/3 (39%)
-even RCP4.5 suggests ice free scenario

Question 15

models predict polar bears eradicated from seasonally ice-covered regions within .. to .. years

Answer 15

50-70

-2/3 polar bears live here

Question 16

sea ice changes cause shifts in trophic interactions through reduced availability and abundance of polar bears main … seals

Answer 16

prey

-also polar bears need to walk or swim more and use more energy