glaciers

Question 1

Glacier

Answer 1

a body of ice formed on land and in motion contained by terrain, most commonly valleys.

Question 2

how is a glacier formed?

Answer 2

-Removing air makes snow solid
Mass of ice that moves over land
-ice sheets
-snow compresses forming layers of glaciers
-glaciers provide fresh water
-indicate global warming
-snow that doesn’t melt before the next year

Question 3

Accumulation

Answer 3

annual snowfall + ice which does not entirely melt in the summer months builds up over time

Question 4

Terminus

Answer 4

where glacier ice starts to melt

Question 5

Ablation

Answer 5

the process of melting ice on a glacier

Question 6

Glacier Mass Balance

Answer 6

The mass balance of a glacier is the gain and loss of ice from the glacier system. A glacier is the product of how much mass it receives and how much it loses by melting.

Question 7

cryosphere

Answer 7

frozen water part of the Earth’s system (covers about 20% of Earth’s surface)

Question 8

Natural Characteristics of Glaciers + Ice Sheets

Answer 8

1. Sea ice
2. land covered by glaciers
3. land covered by ice sheets, including ice shelves
4. land such as tundra covered by snow every year
5. land underlain by permafrost
6. peri-glacial zones on the margins of ice-bound land

Question 9

Tundra

Question 10

Permafrost

Answer 10

Permafrost is a permanently frozen layer on or under Earth’s surface. It consists of soil, gravel, and sand, usually bound together by ice. Permafrost usually remains at or below 0°C

Question 11

Peri-glacial zones

Answer 11

The periglacial environment is a cold climate, frequently marginal to the glacial environment, and is characteristically subject to intense cycles of freezing and thawing of superficial sediments.

Question 12

Natural Processes Causing the Melting of Glaciers + and Ice Sheets

Answer 12

-Variations in Solar Energy
-Volcanic Activity
-Oceanic Circulation Changes
-Plate Tectonics

Question 13

Natural Processes - Variations in Solar Energy

Answer 13

the solar energy received by the Earth is not constant, earth is subject to three independent cycles every 26,000 40,000 and 100,000 years producing natural climatic cycles.

Question 14

Natural Processes - Volcanic Activity

Answer 14

this can cause significant amounts of dust and gases to be injected into the atmosphere. Lead to both warming and cooling, greenhouse gases from volcanoes can lead to warming.

Question 15

Natural Processes - Oceanic Circulation Changes

Answer 15

the direction of ocean currents has changed regularly in recent geological times and many continents have experienced changed climate as a result, as there is an exchange of heat between oceans + the atmosphere.

Question 16

Natural Processes - Plate Tectonics

Answer 16

the redistribution of landmasses has long been caused by plate tectonics. The movement of plates causes variation

Question 17

Human Activities Causing the Melting of Glaciers + and Ice Sheets

Answer 17

-Alteration of the composition of gases in the atmosphere
-Alteration of landscapes
-Direct addition of heat to the atmosphere

Question 18

Human Activities - Alteration of the composition of gases in the atmosphere

Answer 18

this factor is considered by scientists to be the greatest cause of global warming. Increased injection of greenhouse gases such as carbon dioxide, methane + ozone etc. into the atmosphere.

Question 19

Human Activities - Alteration of landscapes

Answer 19

this factor is considered to be the second most important in causing global warming. Removing forests for crops reduces evaporation and changes the dynamics of radiation created by forest canopies.

Question 20

Human Activities - Direct addition of heat to the atmosphere

Answer 20

many of the activities associated with everyday life directly add heat to the atmosphere. Burning fossil fuels for electricity production, transportation, heating, and cooling of residents and workplaces.

Question 21

Last Glacial Maximum

Answer 21

17,000-21,000 years ago, temperatures were 6°C cooler, most liquid water was held in ice caps, sea levels were 125m lower + there were land bridges between landmasses.

Question 22

Holocene Climatic Optimum

Answer 22

De-gelation following the LGM, a period between 9000 + 5000 years ago when global annual average surface temperatures were warmer than today, the climate was wetter, sea level + coasts further inland.

Question 23

The Greenhouse Effect

Answer 23

effect is a process that occurs when gases in Earth’s atmosphere trap the Sun’s heat.
Burning fossil fuels like coal and oil puts more carbon dioxide into our atmosphere.
Too much of these greenhouse gases can cause Earth’s atmosphere to trap more and more heat. This causes Earth to warm up.

Question 24

Fossil Fuels

Answer 24

natural fuels such as coal, oil or gas formed in the geological past from the remains of living organisms.

Question 25

Where does CO2 come from?

Answer 25

• life
• volcanoes
• ocean
• fossil fuels

Question 26

Gases contributing to global warming

Answer 26

• methane
• CFCs
• Ozone (O₃)
• Nitrous oxide (N₂O)

Question 27

What are the impacts of melting glaciers and ice sheets?

Answer 27

• Sea Level Rise
• People Movement
• Agricultural Output
• Freshwater Resources
• Plant + animals communities
• Disease
• Natural disasters

Question 28

Impact - Sea Level Rise

Answer 28

-during 20th century sea levels rose by 20cm
-predicted to rise another 20 – 60cm by 2100
-Since water expands as it warms, as ice melts into the ocean it expands.

Question 29

Impact - People Movement

Answer 29

-people who rely on glaciers + ice sheets for freshwater
-people moving due to their not being traditional food
-people moving since their homes have become inundated.

Question 30

Impact - Agricultural Output

Answer 30

-crops yield will decrease by 30%
-water sources become unreliable + crop failures increased

Question 31

Impact - Freshwater Resources

Answer 31

-increased melting can lead to enlarged glacial lakes causing lake banks to burst
-once a glacier is gone that water source is gone
-glacier stores 75% of the world’s freshwater

Question 32

Impact - Plant + animals communities

Answer 32

-animals lose their habitats as ice retreats
-changes in temp are changing migration patterns
-impacting ecosystems

Question 33

Impact - Disease

Answer 33

-mosquitoes + ticks may expand their range as temp rise
-impacting people + animals living in cold places

Question 34

Impact - Natural disasters

Answer 34

-flooding increased + other natural disasters
-expanding populations + deforestation can make areas suspectable to flooding
-change ecosystems

Question 35

Accelerated melting processes

Answer 35

1. Surface melting due to warmer temperatures which can reveal dirty (dark) ice and speed up melting.
2. Moulins lubricate and accelerate the flow of glaciers to the coast.
3. Sea ice shelves melt as warmer oceans melt the underside of the shelves.

Question 36

Dark Ice

Answer 36

Dark ice speeds up the melting process (less reflection of heat due to the darker colour).

Question 37

Moulins

Answer 37

A vertical cylindrical shaft in the ice by which surface meltwater flows down from the surface to the base of a glacier.

Question 38

Cryoconite

Answer 38

a grey to black coloured mineral composed of windblown sediments such as soot, dust & soil.
Cryoconite can accelerate ice melting (due to reducing albedo- reflectiveness) and lead to the formation of moulins that can cause the ice sheet to melt from its base.