Unit 3: AOS 1 - Land Cover Change Flashcards
1
Q
Conditions in HCO, LGM and Current Day
A
-
LGM (between 21 000 and 18 000 years ago)
- Approximately 6 degrees colder than today
- Sea level was around 125m lower than today - water held in ice sheets and the thermal contraction of water
- Arid and colder
- Australian rainfall decreased - 60% of today’s (NASA)
-
HCO (8 000 years ago)
- Warmer and wetter
- Rainfall 142% of today’s (NASA)
- Ice melted, retreated and thermal expansion → sea level rose
2
Q
Land Cover in HCO, LGM and Current Day
A
-
LGM
- ~30% earth was covered in ice
- Extensive ice cover expanding over the Northern Hemisphere - northern Europe and Asia and much of North America - ↓ forest
- The amount of ice in the Northern Hemisphere was double that of the Southern Hemisphere (except Antarctica) due to ↑ land mass in Northern Hemisphere
- ↑ ice cover in central Europe, central Africa and on the west coast of South America (i.e. patagonian ice sheet)
- ↑ extreme deserts
- Forests and woodlands contained to pockets near equator and did not extend as high in terms of elevation
- Forests of South America (Amazon) and equatorial Africa ↓ due to drier conditions
- North America dominated by forest in the south
- Biomes including grasslands, desert and tundra were more widely distributed than today
- ~30% earth was covered in ice
-
HCO
- Extreme deserts contracted to central Asia, south-west Africa and the west coast of South America
- Ice retreated to high latitude and high altitude regions - similar to present day
- 47% of land mass was forest
- Forest expanded into the northern hemisphere and spread to all continents except Antarctica
-
Present
- ↑ extreme desert in North Africa and central Asia
- Forests similarly distributed to HCO except human activity reducing forest cover
3
Q
Melting Ice Sheets and Glaciers
Definition of Ice Sheet and Glacier
A
- Glaciers
- In motion
- Contained by terrain (eg. frozen river)
- Ice Sheets
- Masses of ice at least 50 000km2
- High latitude above 60 degrees
- Not confined
4
Q
Melting Ice Sheets and Glaciers
Global Melting Ice sheets and Glaciers
A
- Since 1901 Greenland and Antarctic shed 49,000Gt of ice into the ocean (NASA)
- Ice sheets and glaciers hold 11% of world’s freshwater
- 53 mill reliant on meltwater in Ecuador and Bolivia
- 70m sea level rise if cryosphere melted
5
Q
Melting Ice Sheets and Glaciers
Distribution of Ice Sheets and Glaciers
A
- Ice sheets and glaciers cover 10% of the world’s surface
- Ice predominantly in northern hemisphere as the is less land for ice to form in southern hemisphere
- Ice sheets are contained to high latitude regions above 60 degrees.
- For example
- The Greenland ice sheet ~1.7 million square km
- The Antarctic ice sheet ~ 14 million square km
- For example
- Glaciers are located in either high altitude or high latitude regions.
- For example
- The glaciers in the Andes in South America and Mt Kilimanjaro in Africa - low latitudes and high altitude regions.
- Glaciers in Greenland - high latitudes but low altitudes
- For example
6
Q
Melting Ice Sheets and Glaciers
Natural processes
A
-
Surface melting - ↑ surface melt → ↓albedo
- Sea water 0.2 albedo i.e. reflects 20%
- Ice 0.8 albedo i.e. reflects 80%
- Moulins - funnel water to base of glacier acts like a lubricant speeding up glacial movement
-
Basal melting - sea ice shelves melting - warmer oceans melt underside of shelves
- This can cause calving - where ice brakes off the ice sheet into ocean
- Dark ice - caused by crysonites (photosynthetic bacteria, soot and dust) - ↓albedo
-
The Milankovitch Cycle
- Depending where we are will determine amount of sunlight
- Tilt, eccentricity (shape of orbit) and precession (wobble)
- Ocean circulation changes - changes ocean currents impact exchange of heat between ocean and atmosphere - eg. El nino and La nina
- Volcanic activity - reflective dust → lowers temp - gases → warmer temps
- Plate tectonics - as latitude changes due to land mass movement → climate change - occurs over millions of years
7
Q
Melting Ice Sheets and Glaciers
Human processes
A
-
GHGe
- 1.58 degree ↑ land temp and 0.88 degree ↑ ocean temp (IPCC, 2021)
- Average 1.1 degree ↑ - 1 degree due to human processes
- Sea levels have risen by 0.2m since 1800
- 1.9mm/year between 1971 and 2006
- 13.7mm/year between 2006 and 2018
- 1.58 degree ↑ land temp and 0.88 degree ↑ ocean temp (IPCC, 2021)
- CO2 emissions
- 67% of global temp ↑ (IPCC, 2021)
- Safe = 350 ppm - current= 410 ppm
- 149% pre-industrial levels (IPCC, 2021)
- Methane emissions -
- 16% of global temp ↑ (IPCC, 2021)
- 86 times greater impact than CO2 (IPCC, 2021)
- 260% - pre-industrial levels (IPCC, 2021)
- Emissions released primarily from burning fossil fuels and deforestation
- Alteration of landscape - clearing forests for cities - change in albedo thus global temperatures
- Direct Addition of Heat into the Atmosphere - burning of fossil fuels, heating and cooling of residences and workplaces
8
Q
Melting Ice Sheets and Glaciers
Case Study: Greenland - Overview
A
- Pop - 56 000
- 80% inuit
- Poverty - 16.2%
- 83 in every 100 000 commit suicide - highest rate in the world
- Greenland ice sheet makes up 1.2% of global land cover
- Ice sheet covers 80% of Greenland - up to 4km thick
- Autonomous danish dependent territory
9
Q
Melting Ice Sheets and Glaciers
Case Study: Greenland - Impacts
A
- Sea levels have risen by 0.2m since 1800
- Caused predominantly by Climate Change
- Land temp increase 1.58 degrees since 1880
- Ocean temp increased by 0.88 degrees
- 50% thermal expansion
- 42% melting ice
- In the last 32 years there has been a 1.7 degree rise in temperature
- 166Gt lost in 2021
- Ice is thinning
- Ice is forming two months later and melting one month earlier than it should
- Migration south
- 25th year in a row that Greenland has lost more ice than it’s gained
- The average albedo of Greenland’s ice declined by 5% between 2000 and 2015
- 6m sea level rise if ice sheet melted
- Permafrost melt - methane emissions
- Illulissat/ Jakobshavn Isbrae glacier
- 110,000 km2 volume
- Over 65 km long
- Worlds fastest retreat
- 1985 traveling at 7kms per year
- 2006 traveling at 14kms per year
- Retreated over 40kms since 1851
- Velocity has doubled
10
Q
Melting Ice Sheets and Glaciers
Case Study: Greenland - Local Response: Agriculture
Overview
A
- What
- Rise in Agriculture due to increased fertile land in the south caused by ice retreat
- Wider range of crops
- Where sustainable agriculture
- 68% is near Narsaq
- 17% is near Nanortalik
- 13% is near Qaqortoq
11
Q
Melting Ice Sheets and Glaciers
Case Study: Greenland - Location Response: Agriculture
SWOT
A
- Strengths
- Increase crop variety - edible crops
- Boost economy - less reliant on Denmark
- Carbon sepuation
- Narsaq
- 31 sheep farms
- Qaqortoq
- Strawberries and cucumbers
- Weaknesses
- Qaqortoq, Narsaq and Nanortalik summers have been warmer but also much drier - more expecnsive due to irrigation
- Costs more to run than profit made
- Very separated - hard to trade supplies and support one another
- Opportunities
- With the right animal manure, seaweed and even glacial rocks farms can greatly improve the quality and quantity of their crops
- Narsarsuaq produces ~600 pounds of honey to sell each year, the bees are resilient to the hot summers and the cold winters
- Threats
- Pests and insect invasion - due to changing temperatures
- In Narsaq, cabbage root fly, a pest, has been introduced to the environment and is attacking crops like potatoes and turnips
- Evaluation
- Effective in short term
12
Q
Melting Ice Sheets and Glaciers
Case Study: Greenland - Local Response: Shift from hunting to fishing
Overview
A
- Hunting requires boat, snowmobile or dog sleigh - ice thinning prevents this
- Climate change effects distribution of the hunted species
- Caribou affected by change is temp and precipitation - 56% decline
- Change in sea temp and ice coverage
- Decrease in shrimp numbers
- Increase in cod
- 2016 - more than 90% of exports were fish
- 2018 - 50% of GDP from fish exports
- As a result people are starting to fish more than hunt
- 20% workforce are employed by fisheries
- Greenland’s fish exports have increased between 2012 and 2017 at an annualised rate of 4.6%.
- 10% of pop involved in hunting
- 20% workforce are employed by fisheries
13
Q
Melting Ice Sheets and Glaciers
Case Study: Greenland - Location Response: Shift from hunting to fishing
SWOT
A
-
Strengths
- Employment important due to poverty
- Eg. Niaqornat
- Pop 59
- Heavily reliant on fishing
- Fishery closed briefly - if not reopened people would have had to leave
- Eg. Ilulissat Icefjord
- Increase in cod number and size
- Improved diet and income for local community
- Decline in icebergs surrounding entrance allows for quicker and easier access to marine life in fjord
-
Weaknesses
- Decline in traditional hunting practises
- Eg. Inughuit
- Northernmost tip of Greenland
- Pop - 800 across 4 settlement makes up the Thule region
- Woman from a settlement
- 15 years ago sea ice 3km think
- Now hunters falling through ice
- Decline/ disappearance of dogsled hunting
- Increase depression and suicide rates
-
Opportunities
- Fisheries provide increase in jobs and income for those that can no longer hunt
-
Threats
- Inughuit forced to migrate south
- Loss of culture as they will assimilate to broader Inuit culture
- Recently 1 of 4 settlements in Thule was closed
- Inughuit forced to migrate south
-
Evaluation - whether it’s effective in mitigating impacts of climate change
- Not effective in adapting to climate change
- Jobs in fishing - should be hunting using traditional methods
- Assimilation - loss of culture - detrimental to well being of Inuit people
14
Q
Melting Ice Sheets and Glaciers
Case Study: Greenland - National Response: Last Chance Tourism
Overview
A
- Tourism contributes $27 USD million to Greenland’s economy
- 2000 - 34 000 overnight guests - 2019 - 105 000
- Government promoting last chance tourism
- Visit Greenland Website - details on destinations - how/ where to travel
- 2019 - 725 people were employed in the tourism industry
15
Q
Melting Ice Sheets and Glaciers
Case Study: Greenland - National Response: Last Chance Tourism
SWOT
A
-
Strengths
- $27 USD
- Rely less on mining
- Respond to impacts of melting ice sheets and glaciers
- In adventure tourism - the movement of people from one place to another outside their comfort zone for exploration
- 65% of the revenue goes to local communities
- Makes people aware of the impact of Climate Change
- Nuuk recently achieved a Bronze Benchmarking which means they have completed the first three steps of a six-step process towards becoming a sustainable destination
- $27 USD
-
Weaknesses
- Fossil fuel intensive air travel - on a global scale aviation contributes 2.1% of the global emissions and an estimated 4.9% to global warming
- Between 2016 and 2018 tourists arriving by air increased by 3.3% in Greenland
- Decline in traditional tourism
- Dog sledding
-
Opportunities
- Construct larger airports in Ilulissat and Nuuk
- Education of people
- Stability to economy who currently relies on exports causing fluctuation in inflation and employment
-
Threats
- Cultural ceremonies put on display
- Loss of Inuit culture due to migration away from home in search for jobs
-
Evaluation - whether it mitigates climate change impacts
- Boosts economy
- Provides employment
- Overall not effective or sustainable in mitigating the effects of climate change and melting ice sheets and glaciers
- Air travel
16
Q
Melting Ice Sheets and Glaciers
Case Study: Greenland - Global Response: Conference of Parties #26 (COP - 26) Climate Summit
Overview
A
- Includes 197 Nations - agreed to new environmental pact called United Nations Framework Convention on Climate Change in 1992
- Occur every 5 years
- COP-26 in Glasgow
17
Q
Melting Ice Sheets and Glaciers
Case Study: Greenland - Global Response: Conference of Parties #26 (COP - 26) Climate Summit
Aims
A
- Secure global net zero by mid-century
- Keep 1.5℃ global warming within reach
- Adapt to protect communities and natural habitats
- Mobilise finance (secure funds)
- Complete negotiations on the Paris Agreement (2016) rule book
18
Q
Melting Ice Sheets and Glaciers
Case Study: Greenland - Global Response: Conference of Parties #26 (COP - 26) Climate Summit
SWOT
A
-
Strengths
- Global stock take
- National Determined Contributions (NDC’s) are assessed
- Countries provide one each year - reviewed every 5 years
- Decisions made in a Draft are legally binding to to the Paris Agreement (2016)
- Fossil fuels were mentioned for the first time
- Phase-out of inefficient fossil fuel subsidies
- Prior to COP26 - global temp rise 3 degrees - now 2.4 degrees - by 2100
- 137 countries committed to halt deforestation and begin restoration by 2030
- 103 countries and 15 major emitters signed Global Methane Pledge which limits methane emissions by 30% by 2030
- Global stock take
-
Weaknesses
- Agreed to phase down fossil fuels instead of phase out
- Countries who haven’t met targets are allowed to purchase emission reduction from Nations who have exceeded their targets - added to Paris Rulebook
- Consensus required - 197 countries - lowest common denominator
- No way to enforce targets
- IPCC reports (which advise leaders) only released every 6-7 years
- 503 fossil fuel delegates - more than any other country
- China’s NDC set net zero emissions target by 2060 - they are the biggest contributor
- No plan to reduce aviation emissions
- Contributes 2.1% of the global emissions and an estimated 4.9% to global warming
- Paris Agreement provision of “net zero in the second half of this century” - gives countries too much leeway - eg. India net zero by 2070
-
Opportunities
- 2023 - US$100 billion to go to developing nations per year
- There are calls for this to double
- Glasgow Climate pact calling on countries to present stronger NDC’s in 2023 instead of 2025
- 2023 - US$100 billion to go to developing nations per year
-
Threats
- Emission offsetting can have negative impacts
- Threatens indigenous and rural people and ecosystems by taking their land for tree plantations
- Next phase of climate denialism
- Countries may interpret draft form COP26 differently
- 2.4 degree temp rise too high - safe increase at 1.5 degrees
- Many underprivileged countries might leave if they continue to be ignored
- Emission offsetting can have negative impacts
-
Evaluation of whether the melting of Greenland’s ice will be slowed
- Step in right direction - prior to COP26 - global temp rise 3 degrees - now 2.4 degrees
- still not 1.5 degree aim
- Not on targets set by climate scientists - not sustainable long term if we remain on the current trajectory
- Eg. NASA reported that an increase in temp by 2 degrees would result in 0.2 m sea level rise caused by thermal expansion and melting ice hence Greenland ice sheets will continue to melt
- Step in right direction - prior to COP26 - global temp rise 3 degrees - now 2.4 degrees
19
Q
Deforestation
Definitions
A
- Forest
- “O.5 or more hectares covered by trees higher than 5m with a canopy cover of more than 10% or by trees able to achieve this. Does not include agricultural and urban land areas.” - (FAO)
- Deforestation
- “The conversion of forest to another land use or the long-term reduction of tree canopy cover below the 10% threshold.” - (FAO)
20
Q
Deforestation
Global Forest Cover Distribution
A
- 4 billion hectares of forest
- 31% of world’s total land area is forest
- Forests are not evenly distributed
- 75% of forests in high to middle income countries
- Distribution by regions
- 45% in tropics
- 27% in boreal countries
- 16% in temperate countries
- 11% in subtropical countries
- Top 5 countries with most forest (make up 53.8% of all forests)
- Russia - 20%
- Brazil - 12%
- Canada - 9%
- U.S.A - 8%
- China - 5%
- 6 countries have no forest cover - eg. Greenland
- Types of forest
- 34% primary (undisturbed)
- 59% secondary (recently disturbed by human activity)
- 7% planted
21
Q
Deforestation
Global Deforestation
A
- The area of primary forest worldwide has decreased by over 80 million hectares since 1990 (FAO, 2020)
- 12.2m hectares of tree cover was lost in the tropics in 2020 (WRI, 2021)
- Forest loss and damage is the cause of around 10% of global warming (WWF, 2022)
- 20 percent of the world’s greenhouse gas emissions come from the clearing of tropical forests
- However, forests have still increased over the last 30 years
22
Q
Deforestation
Case Study: PNG - Overview
A
- Population - 8.9 million (World Bank, 2020)
- Poverty - 85.7% according to multidimensional poverty measure (World Bank, 2020)
- 2.6% unemployed
- 33.6 Mill hectares (Mha) of forest (FAO, 2015)
- PNG’s forest covers 80% of the country’s land area - 60% of the forest are undisturbed (UNFCCC, 2017)
- 3rd largest rainforest in the world
- Most biodiverse
- 5-7% of all known animal species live in PNG
- The indigenous people own the land
- 800 language groups
- 1.57Mha of tree cover lost between 2000 and 2020 equivalent to;
- 3.7% decrease in tree cover
- 1.15 giga tonns (Gt) of CO₂ emissions
- 2021 lost 73.3 thousand hectares of natural forest = 55.0 mega tons of CO₂ emissions (2021, Global Forest Watch)
- ~70% logging illegal
- SABL’s - 11% of PNG’s land cover - made illegal in 2016 but still exist
- 5 times as much GHGe released from forest degradation than from deforestation
- 98.1% of forest degradation from commercial logging
- 55% of deforestation for family agriculture
- 75% if pop - subsistance agriculture
- 26% of deforestation from commercial agriculture
23
Q
Deforestation
Case Study: PNG - Impacts of Deforestation
Social
A
-
Negative
- Diseases such as malaria and cholera spread - eg. stagnant/polluted waters
- Tribes coming together could result in loss of culture
- Trees are shelter and protection for animals and people
- Strong spiritual connection to trees - many people believe spirits inhabit forests
- Loss of ecological services which include;
- Water
- Medicine
- Food
- Timber
- Fibre
- Landslide protection
- Prevent soil erosion
- Treatment of women by logging employees
-
Positive
- Logging industry could provide locals with jobs
- Eg. walkabout sawmills - gives locals transportable sawmills - provides income
- Logging industry could provide locals with jobs
24
Q
Deforestation
Case Study: PNG - Impacts of Deforestation
Economic
A
-
Negative
- Increase of jobs but low pay → unemployment low but poverty high
- 70% of logging occurring illegally the PNG → Government loses tax income
- Locals having to pay for ecosystem services - eg food and medicine as they no longer exist in environment and are only available as commercial products
- Positive
25
Q
Deforestation
Case Study: PNG - Impacts of Deforestation
Environment
A
-
Negative
- Loss of biodiversity - destruction of habitat is
- New roads - fragmentation - droughts and fires
- Less CO2 absorption
- Burning releases CO2 into the atmosphere
- Reduces the critical water cycling
- ↑ flooding → soil erosion
26
Q
Deforestation
Case Study: PNG - Local Response: Walkabout Sawmills
Overview
A
- Impacts its responding to - Poverty within the indigenous communities of PNG
- Small scale, portable timber milling machine
27
Q
Deforestation
Case Study: PNG - Local Response: Walkabout Sawmills
Aims
A
- To prevent commercial logging in rainforests by giving indigenous people an alternative source of income
28
Q
Deforestation
Case Study: PNG - Local Response: Walkabout Sawmills
SWOT
A
-
Strengths
- Easy to operate
- Affordable
- Money goes directly to locals
- Quicker/better than only chainsaws
- Roads not needed - fragmentation prevented - roads ↑stagnant waters thus malaria
- For every tree felled 3 saplings are planted
- Keep some wood in community (houses etc.)
- $1 mill acres of forest protected
- More money generated than from commercial logging
- $450/m3 vs. $3/m3 - 20 times as much
- Training and education program
- Restoration (tree plantation)
- Maintenance
- Business management
- Locals maintain control of what happens on their land
- Minimal disruption to life and society structure
- Selective logging rather than clearfelling - less impact on waterways + biodiversity
-
Weaknesses
- Maintenance when they break down (2012 AU found this not to be a large problem)
- Enables logging (but much more sustainable)
- Limited opportunities for women - uneven income/power distribution
- No permits required - can log up to 500m3 - not monitored
- Due to weight of mills becoming stationary rather than mobile as intended → logging of one area (especially along tracks)
- Relies on admin + management skills of locals, which are undeveloped
- 2012 AU Gov. report found this was the biggest weakness
-
Opportunities
- Training and education program (see above)
- More sawmills to be distributed
- Lighter materials for sawmills → more mobile
-
Threats
- Maintenance issues increasing
- Competition from logging companies
- Maintaining a market of buyers
- Local disputes over resource ownership + management
-
Evaluation
- Effective in preventing commercial logging
- Lowers poverty by providing education, income and employment
- Not bad for forest as saplings planted and roads not required
29
Q
Deforestation
Case Study: PNG - National Response: National Forest Inventory (NFI)
Overview
A
- National Forest Inventory (NFI)
- Gathers accurate information on flora and fauna, carbon stocks, estimated GHGe from deforestation and forest degradation
- Funded by EU and UN-REDD+
- Uses Open Foris Collect Software - developed in Rome
30
Q
Deforestation
Case Study: PNG - National Response: National Forest Inventory (NFI)
Aims
A
- To support the PNG Forest Authority
- To implement a continuous and multipurpose NFI which is a key component of a National Forest Monitoring System that PNG is required to establish to participate in the UNFCCC REDD+. Scheme
- For inhabitants to utilise what’s in their country
31
Q
Deforestation
Case Study: PNG - National Response: National Forest Inventory (NFI)
SWOT
A
-
Strength
- Created Climate Change and Forest Monitoring Web-Portal
- Make eligible for REDD
- Educates and provides jobs for locals
- 32 officers trained in flora and fauna management
- 10 officers can identify 80% of plant species
- 20 officers across PNG can recognize 80% of tree species
- First phase of assessment using remote sensing and second phase of field inventory based on pilot clusters - both completed
- 2014 - 2019
- Monitoring methods include;
- Point counts
- Mckinnon lists
- Songmeter boxes
- Multipurpose NFI will collect
- Timber volume
- Ono-timber forest products
- Carbon stock
- Soil characteristics
- Biodiversity (flora and fauna)
- Socio-economic aspects of PNG forests
- Created Timber Legality Verification System
- Acquire consent from landowners
-
Weaknesses
- Due to poverty rates - information not accessible to indigenous people
- Disturbs sacred forest that hold strong spiritual connection in indigenous culture
- Susceptible to error - especially estimated carbon stocks
-
Opportunities
- Make eligible for ↑ REDD+ payments thus preventing deforestation
- Prevent illegal logging due to constant monitoring
- Threats
-
Evaluation
- Effective as has made PNG eligible for REDD+
32
Q
Deforestation
Case Study: PNG - Global Response: REDD+
Overview
A
- Responding to - deforestation on a global scale causing release of carbon emissions which in turn contribute to climate change
- REDD+ - Reducing Emissions from Forest Degradation and Deforestation
- Voluntary approach to mitigate climate change developed by UNFCCC
- Gives monetary value to carbon stocks making forests more valuable standing than as timber
- Established in 2008
33
Q
Deforestation
Case Study: PNG - Global Response: REDD+
Aims
A
- To reduce CO2 emissions by slowing or halting deforestation and increasing removal of GHGe by conserving and managing forests
34
Q
Deforestation
Case Study: PNG - Global Response: REDD+
SWOT
A
-
Strengths
- Incentives to not cut down trees by giving them monetary value
- ↓ CO2 into atmosphere = ↓ Global temp changes
- ↓ poverty by paying landowners to preserve their forests
- Protects the cultural and spiritual heritage of forests
- Prevents impacts of deforestation
- ↑ flooding
- Soil erosion
- ↑ spread of diseases such as malaria and cholera
- Destruction to biodiversity
- Removal of ecosystem services
-
Weaknesses
- PALM
- Permanence - trees will die eventually
- Additionality - paying for keeping forests standing that were never going to be logged
- Leakage - moving around to deforest non-REDD regions
- Measurement - expensive, difficult, time consuming + prone to large errors
- Slow to gain momentum and coverage (10 years for first carbon credit to be sold)
- Doesn’t stop or ↓ emissions in high polluting regions
- “Carbon cowboys” - people exploiting local communities through carbon credit and trading schemes similar to commercial logging companies
- PALM
-
Opportunities
- More participation - less leakage
- Stricter legislation - less exploitation of indegenous peoples by “carbon cowboys”
-
Threats
- Carbon credits could become another ‘resource curse’ like oil, diamond or gold
- Become another carbon offset mechanism that doesn’t actually mitigate climate change
-
Evaluation - of aims
- Hasn’t lowered GHGe as MEDC’s still pollute
35
Q
ICESAT - 2
A
- Remote Sensing
- NASA owned satellite (US)
- Currently in orbit
- Launched in California 15 September 2018
- Measures topography of earth and thus can determine ice sheet and glacier melt
- Data stored on board - includes measurements from 2003 and 2019 which are compared to determine change in ice and glacier mass
-
Function - carries instrument - Advanced Topographic Laser Altimeter System (ATLAS)
- 1 laser split into 6 beams
- 10 000 pulses per second
- Each pulse ~ 20 trillion photons - only ~ 12 trillion reach earth and return to satellite
- Measures time taken for lasers to return to satellite which provides distance hence topography
- Orbit - polar (orbits around the poles)
-
Data found - 2021
- Surveyed 34 outlet glaciers
- 3 retreated more than 3.5 km/year and only one had no change in thickness
- Measures ice sheet thickness via seasonal comparison
- Surveyed 34 outlet glaciers
