Ice sheets & Glaciers (Greenland) - Final Exam prep

Local response to melting glaciers and ice sheets (ilulissat hydroelectric project)

aim: replace diesel generated energy in green energy

uses meltwater coming from permafrost layers and glaciers

Located in west Greenland

started in September 2013

produced energy for ilulissat (pop of 4,500)

plants capacity is 22.5 megawatts

45k’s NE of town

turbines are as deep as 200m below surface

provides 20-30% of greenlands power

funded by gov

clean energy = less heat and less reliance on fossil fuels

National response to melting glaciers and ice sheets (tourism)

introduced in 2021 and ran throughout 2021-2024, post pandemic

aims to rebuild tourism post-covid-19 to distribute tourism seasonally and geographically

interconnected with broader national tourism to open new and larger

airports in ilulissat and nuuk

global tourism is projected to geow 13.3% per year from 2019-2026

Global response to melting glaciers and ice sheets (COP)

Conference of parties

under the UN framework convention on climate change (UNFCCC)

made up of 200 countries as of 2024

aims: to limit climate change at 2^oC above pre-industrial levels

avg temp as risen 1.5^oC since 1850 - more manageable than 2^oC

Europe greenhouse gas pollution dropped by 18% in 2024

COP 26 (2021) was last chance to save planet from effects of more than 1.5^oC warming

2015 Paris agreement was first time countries held themselves accountable - legally binding

Geospatial response to melting glaciers and ice sheets (PROMICE)

began in 2007 - 18 years of solid data now

ran by the department of glaciology and climate at the geological survey of Denmark and Greenland 

monitors/assess’:

• ice thickness

• ice extent

• signs of ice loss

• mass loss on ice sheet specifically

• change in ice sheet over time as a result of global warming

done by:

• airborne surveys to gather data using LIDAR & RADAR (Light/Radio detection and ranging)

• GNSS units used to measure ablation 

• automatic weather stations in Greenland

keeps well documented and open source database

Location (Absolute and Relative)

71.7^o N, 42.6^o W

In the north Atlantic ocean, off northeastern coast of Canada

Human characteristics

Speak greenlandic and Danish

pop concentrated on southwest coast

0.14 people per km²

56,000 population

major cities: Nuuk, sisjimiut & ilulissat

self governed

Geographic characteristics

Geologically apart of North America

1.71 million km²

80% ice

avg thickness of ice is 2km

max thickness is over 3km, central east

10% of earths ice

10% of earths freshwater

ice per km² is 1.7

215 glaciers

HCO (Holocene climactic optimum)

warm period from 9,000-5,000 years ago, started 15,000 years ago after age age (glacial termination)

large ice sheets covering NA and Europe started melting

event consisted of 4^oC increase near north pole

southern Europe experienced cooling

avg temp change declines rapidly due to latitude

why?

• Milankovitch cycles - change in earths orbit = increased solar radiation in the horthern hemisphere

• Greenhouse gas levels - co2 & methane concentration in the atmosphere began to rise due to human activities (deforestation & agriculture)

compared to today

• temps warmer than now

• tropics and parts of southern hemisphere were cooler than average 

LCM (Last Glacial Maximum)

18,000-20,000 years ago

last ‘ice age’ where land ice was dominant

8% (today is 3% )of world surface was covered by ice (including land & sea ice)

25% (today is 3%) of earths land surface was covered in ice

sea level was approximately 112-125cm lower than today

surface temp was 4-6^oC colder than average median temp

Cooling was distributed unevenly

• Antarctica stayed the same 

• North Pole changed - ice formed over land meaning it melted quicker 

forest cover was less expensive, climate caused cooler and drier rainfall

grassland became more widespread

africa had grasslands in the south & deserts in the north (closer to equator)

aisa had a mix of tropical deserts in the west, alpine deserts in the north

grasslands in indian subcontinent 

Anatomy of an Ice Sheet

Outlet Glacier

Ice Shelf

Icebergs

Exposed rock

Sea Ice

Moulin

Anatomy of a Glacier

Horn

Arete

Terminal moraine

maternal moraine

Cirque

Calving

General process for melting

accumulation

• temps are cold

• snow collects, adds to mass

• starts with first autumn snow

• older snow compacts

ablation

• mass starts to reduce (melting, calving or sublimation/evaporation)

• starts late spring

• warm air & sun melts snow and ice into water

• calving happens, otherwise slow shrinkage

• all new snow disappears from lower reaches of glacier

• remaining snow form hard layer of firm

• new equilibrium line is made 

Human and natural causes for melting

natural

variation in solar energy

• not consistent 

• milankovitch cycle correspond with periods of glaciation 

volcanic activity

• significant amounts of dust and gas ejected into the air = both warming and cooling

deep water currents

• aka thermohaline circulation

• driven by differences in water density due to temp and salinity 

human

localized addition of heat

• activities of everyday living into the atmosphere (industrial processes - heating, cooling, transport)

alteration of landscapes

• changed in albedo (light refraction)

• clearance of forests

• urbanization

• changed in soil moisture

Interconnection between human and natural causes of melting ice in Greenland

amplification

• humans accelerate naturally occurring processes

• like fluctuations of cold and warm periods

• rate of melting that is faster than what would occur through natural cycles alone

• release of more greenhouse gasses (co2) from burning fossil fuels has strengthened the natural greenhouse effect

• human-induced warming is laid on top of the natural cycles - increasing global average temp

positive feedback loop

• Ice reflects most sunlight back into space, helps keep planet cool

• Ice melts naturally after ice age - darker ground exposed = absorbs more sunlight as heat - more melt

• Humans cause initial melt from activities - natural melt is accelerated more with more ground exposed

Causes for melting ice sheets (plate tectonics)

redistribution of land masses change climates as continents move into different latitudes

changes sunlight reflection and ocean heat balance

long term process

Causes for melting ice sheets (increase in global temperatures)

human and natural

global temps have increased by at least .94^oC since 1880

estimated 40% of ice in the arctic melting is due to warming

more ablation over accumulation

could be from volcanic activity or output of greenhouse gasses

Causes for melting ice sheets (cryoconite)

airborne material from industry, desert dust and volcanic particulate 

melting is increased because it settles on ice pats

reduces albedo (light refraction) and accelerates melting

Causes for melting ice sheets (population change)

60% of all emissions come from cities

emissions come from reduction of forest of forest cover and mangroves (carbon sinks)

methane from thawing permafrost enhances emissions

421 ppm of co2, pre industrial co2 was 250 ppm

impacts of melting ice on the economy

economy (fishing)

• warmer water brings different fish species - shrimp, cod, salmon

• increase in fishing industry

• large companies adapt better than small independent companies - struggle to buy new equipment (e.g bigger boats, nets, processing machinery, crab pots & trawlers)

• fishing export has grown from 138 million USD (1980) to 470 million USD (2014) - 34 years

impacts of melting ice on the society

society

• changing diets - replacing traditional foods (seal & whale) to imported food

•                         - native fish are leaving because of increase of freshwater from melting ice

• people leaving/migration - women aged between 15-25 leaving for education or better job offers and resources and more housing accessibility

• average of 2,544 people leaving every year (data from 2012-2022)

impacts of melting ice on environment

environment

• water salinity changing because of glacial meltwater

• more land for agriculture - land increased 30%, no. of farms decreased by 20% both in the last 20 years

• lack of nutrients in soil after melting means bad soil quality

• rate of melting increased - 5x greater in last 20 years than pre-industrial levels