unit one

Question 1

how much are sea levels raising by average per year?

Answer 1

2.6cm

Question 2

how much do glaciers move per day?

Answer 2

25cm

Question 3

what is glacier mass balance?

Answer 3

the difference between inputs (accumulation) and outputs (ablation)

Question 4

what is the mass balance when inputs > outputs?

Answer 4

positive mass balance causing a glacier to grow

Question 5

what is the mass balance when outputs > inputs?

Answer 5

negative mass balance causing a glacier to shrink

Question 6

where is the zone of accumulation?

Answer 6

colder higher altitude areas

Question 7

where is the zone of ablation?

Answer 7

warmer lower altitude areas

Question 8

what occurs between the zones of accumulation and ablation?

Answer 8

the line of equilibrium where mass balance is equal

Question 9

how is glacier ice formed?

Answer 9

glacier ice is formed primarily from compacted snow with contributions of inputs hail or sleet which freeze on top of or inside the glacier

Question 10

what does accumulation result from?

Answer 10

direct snowfall or other precipitation, icefalls, blown snow and avalanches

Question 11

what does ablation result from?

Answer 11

melting, evaporation (sublimation) or the breakaway of ice blocks and icebergs called calving

Question 12

how will the area of zones of accumulation and ablation vary over a year?

Answer 12

the inputs will outweigh the outputs and the glacier will grow/advance in winter and the outputs will outweigh the inputs and the glacier will retreat in summer

Question 13

how does ice form from snowflakes?

Answer 13

when snowflakes fall they compact. snow that has become compacted and experienced one winters freezing and a summers melting is referred to as firn. after a number of years when the firn has reached a depth of 20m the air is squeezed out and glacier ice forms

Question 14

what percentage of glaciers around the world have a negative mass balance?

Answer 14

75%

Question 15

what is the melting of glaciers causing?

Answer 15

sea levels to rise, and carbon dioxide to be released into the atmosphere causing further warming along with albedo decreasing, which contributes to melting

Question 16

what happens during interglacial periods?

Answer 16

glaciers have a negative mass balance leading to them retreated

Question 17

what happens during glacial periods?

Answer 17

glaciers have a positive mass balance leading to the long term growth of glaciers

Question 18

what was the last glacial period?

Answer 18

the devensian

Question 19

what glacial/interglacial period are we in now?

Answer 19

interglacial - holocene

Question 20

what are the long term changes between glacial and interglacial periods caused by?

Answer 20

the earths stretch tilt and wobble/ eccentricity, tilt and precession

Question 21

what timeframe does the earths tilt operate at?

Answer 21

41,000 years

Question 22

what affect does tilt have on climate?

Answer 22

more extreme seasons

Question 23

how long does one wobble/precession cycle take?

Answer 23

20,000 years

Question 24

what time frame does the eccentricity/stretch of the earths orbit operate at?

Answer 24

100,000 years

Question 25

what is the orbital cycle?

Answer 25

the change in the shape of the orbit from circular to elliptical every 100,000 years

Question 26

what does the tilt of the earths axis change from

Answer 26

22.1 to 24.5

Question 27

what is albedo?

Answer 27

how reflective the earths surface is

Question 28

what can milankovitch cycles cause?

Answer 28

warming and cooling of the environment.

Question 29

describe the thermohailine ocean circulation

Answer 29

the ocean circulation brings warm salty water northwest europe which leads to warm winter conditions for example the average winter temperature in england is 5 degrees and in russia it is -8 degrees despite them both being at the same latitude

Question 30

when was the younger dryas?

Answer 30

13,000 to 11,000ybp

Question 31

what are the causes of short term climate change?

Answer 31

solar forcing, volcanic eruptions and anthropogenic factors

Question 32

describe solar forcing and how it causes short term climate change

Answer 32

solar forcing refers to the energy released by the sun, linked to sun spot activity. sun spots are areas of high solar output which have caused periods such as the little ice age

Question 33

what are sunspots?

Answer 33

areas of high solar output which fluctuate on an 11 year cycle

Question 34

describe the little ice age

Answer 34

from the mid 1600s to 1700s maunder minimum occured with low levels of solar output. sea ice expanded and the baltic sea froze over.

Question 35

how do volcanic eruptions cause short term climate change?

Answer 35

volcanic eruptions propel sulphur dioxide and ash into the atmosphere which reflect incoming solar radiation

Question 36

how do anthropogenic factors cause short term climate change?

Answer 36

human activity is increasing the concentration of green house gasses resulting in an increase of global average temperatures from 1.2 degrees since 1880.

Question 37

what areas are glaciers typically found in, in reference to latitude and altitude?

Answer 37

areas of high latitude and high altitude

Question 38

why are glaciers found in areas of high latitude?

Answer 38

they have lower temperatures due to less insolation which reduces ablation and increases the proportion of precipitation

Question 39

why are glaciers found in areas of high altitude?

Answer 39

there are lower temperatures as temperature decreases with increased altitude