Leathers- AI Questions? Flashcards
Outline the formation of Deep Sea Trenches?
- associated with convergent plate boundaries
- the subducting plate is “dragged” down into the mantle via the process of slab pull
- the DOWNWARPING of oceanic plate creates v-shaped depression in the ocean floor
- this v-shaped trench is formed parallel, but not close to, the coastline
- Where oceanic meets oceanic, the denser of the two is subducted
eg: Nazca and South American= Peru Chilies Trench
Outline the process of “slab pull”?
- Associated with the convergence of plates, where one plate is subducted under another into the Benioff zone
- The subducting plate is generally more dense and less buoyant than the other plate so it is forced to sink
- Gravity acts on the “leading edge “of the subducting plate, helping to “pull “the rest of the plate with it
Outline the processes that lead to the formation of fold mountains?
- A product of the convergence of tectonic plates
- Continental and/or ocean plates are forced together
- This may result as a result of opposing convection currents or slab pull/ ridge push
- “crumpling effect” whereby continental mass is warped and forced upwards
eg: The ANDES
History of Volcanic Theory?
1912- Alfred Wegner
1940’s-50’s - Mid Atlantic Ridge
1930’s- Arthur Holmes= convection currents
Landforms at Constructive Boundaries?
C constructive
O ocean ridge- mid atlantic
R rift valley
Landforms at Destructive Boundaries?
D destructive Margins
F fold Mountains
D deep Sea Trench
Explain the formation of Oceanic Ridges?
- Takes place at oceanic areas where the plates are diverging/ pulling apart
- The area in-between the plates is filled in by basaltic upwelling/ upwelling of magma
- This causes the formation of land and can create SUBMARINE VOLCANOES eg: ICELAND
Explain the formation of Rift Valleys?
- Form at boundaries of divergence where continental plates are pulling apart that are less dense
- cracks/ faults appear within the crust
- areas of crust “drop down” between parallel faults
- the area between parallel faults is called the HORST
eg: The East-African Rift System= features Kilimanjaro
Describe the formation of Fjords?
- they were formed from glaciers, with the movement of glaciers through GLACIATION causing erosion of the landscape
- these glacial valleys become drowned as they are below sea level and become drowned
- they typically are in a U shape, have steep sides and can be 1000m deep
- not deepest at the mount like rias, but instead at a “THRESHOLD”
- EG: SOGNE FJORD IN NORWAY
Describe the changes in Sea Level over the last 20,000 years?88i
18,000 years ago= the last Glacial Maximum
10,000 years ago= 110m below current levels
10,000 years ago= “Doggerland” was still present
- connected the Baltics to Eastern Britain
- now covered by the North Sea
4,000 years ago= current level
1930+= dramatic increase in sea level
Main Methods of Carbon mitigation?
- CSS= Carbon Sequestration and Storage
- geo-sequestration= underground
- Replanting, Afforestation, Silviculture
- Renewable- wind, tidal, solar
- COP26- 2021- november
- Paris Agreement- 2015
- Kyoto Protocol- 1997
IPCC- CARBON BUDGET- 1.5degrees celcuis
What does effusive mean?
A non-explosive eruption
LOW SLICA AND VISCOCITY= BASALTIC
What does the IPCC predict about climate change in the future?
Averaged over the next 20 years there is set to be an exceeding of 1.5oc
(The CARBON BUDGET)
Currently a 66% chance of exceeding the budget
What temperature and speed do Pyroclastic Flows move at?
1000 oc +
700km/h
What percentage of volcanoes and earthquakes take place in the Pacific Ring of Fire?
75% of all ACTIVE Volcanoes on earth
90% of Earthquakes
What has been the increase in climate from 1900- 2020?
+1.08 degrees Celsius increased from 1900-2020
Greenhouse gases absorb Long Wave Radiation
How much is sea level currently rising by per annum?
2mm/ annum
Predicted that by 2100= 8mm/ annum
What are your two contrasting case studies of Tropical Storms?
Hurricane Katrina- August 2005
Cat 3
200 km/h
1,842 dead and 300bn in economic damage
Cyclone Nargis- May 2008
Cat 4
215 km/h
138,500 dead and 4bn in economic damage
Give two examples of ways that people are attempting to limit human impacts in the Amazon Rainforest?
ACTO- 8 Brazilian countries- Latvia, Venezuela
Brazilian Forest Code- 50-80% of there land needs to remain as forest
How much of the Holderness coastline is eroded annually and how much is eroded in a stormy year?
2metres/ annum
Large fetch and strong winds across the North Sea= 7metes/ annum
Give three social impacts of the 2005 Kashmir Earthquake?
8th October 2005
3 million people made homeless
80,000 died
40,000 RELOCATED to a new town after the town “Bakalot” was destroyed
Compare 2005 Katrina and 2008 Myanmar?
Katrina- 300bn in US dollars of damage
1,833 dead
30,000 made homeless
30 oil rigs destroyed on the Louisiana coast
Nargis- 4bn in US dollars of damage
more than 140,000 dead
Evaluate the impacts of a Wildfire event?
2009- Black September Victoria Millions of species burnt and killed 4bn AUS dollars 2000 houses burnt
Physical and Human factors affecting the level of impacts within a hazardous environment?
PHYSICAL- nature of the plate boundary, additional hazards (tephra), lava type
HUMAN- warning systems, aid given from charities, risk sharing, populations BELEIFS and APPROACHES= “fatalism” and “cultural detriments”
Human processes driving change in the carbon cycle?
= ANTHROPOGENIC
-farming practices- pedosphere, “enteric fermentation”
“Enteric methane emissions from ruminant animals raised for their meat and milk account for as much as 30% of global anthropogenic methane emissions”
-land use change- urban sprawl and suburbanisation
“slash and burn technique”
-Burning of hydrocarbons- 2013= 36Gc released globally
Define sub-aerial weathering?
Subaerial processes are land-based processes and occur above the waterline.
They include weathering and mass movement, which happen on the cliff rocks.
These processes operate on the cliff lithology to weaken them and provide material for erosion (attrition)
Difference between mechanical and chemical weathering?
SUB- ARIEL weathering
Mechanical= broken down WITHOUT change to chemical composition
Chemical= broken down WITH change to chemical composition Hydroloisis= the breakdown of minerals to form new clay minerals Cavitation= the breakdown of rocks due to rainfall- carbonic acid Oxidation= adds oxygen to minerals- IORN COMPOUNDS- eg: sandstone
Give two ways that humans are attempting to conserve the Amazon Rainforest?
ACTO- 8 Amazonian countries- Bolivia, Brazil, Colombia
Brazilian Forest Code- 50-80% of land should remain as forest
Give figures for average and largest rates of erosion at the Holderness coast?
Average: 2metres/ annum
Largest: in a stormy year when the North Sea fetch is large= 7metres/ annum
Give statistics from the 2009, February Wildfires (Black Saturday Fires)?
IMPACTS 173 fatalities 400 individual fires 450,000 ha of land burnt RSPCA- over 1 million animals burnt 2009- created a new system called the FDI= the fire danger index
CASUSES
3 consecutive days above 43 degrees
REPONSES
10 billion tonnes of H20 shifted
WFF facts about illegal logging in the Amazon?
WFF states that 80% of the Amazon Rainforest was illegally logged in the 1990’s
12/13 companies investigated proved to be engaging in illegal activities
What is the large scale, Conservation International goal placed down in 2017?
Planned to take place over the next 6 years
73 million trees to be replanted
Replace the 20% of the Amazon that has been lost due to Agriculture in the last 40 years
How would you draw out a Fjord?
LABELS: “flooded glacial valley, U shaped, Very deep water, Waterfalls flowing down valley sides”
Sognefjord, Norway is the longest (205km) and deepest (1308 metres) in Norway.
Define negative and positive feedback?
With positive feedback impacts can be exacerbated once climate change starts to occur as natural processes
tend to compound one another,
increasing climatic instability and the likelihood of extreme conditions.
In contrast, negative feedback is likely
to have a more stabilising impact by depressing rates of the natural processes and moderating rates of atmospheric change.
Explain the development of a saltmarsh environment?
ESTUARY- BEHIND A SPIT- “as the spit builds the area becomes sheltered”
Silt is deposited to form an inter-tidal mudflat
Flocculation- “WHICH IS the dropping of silt”
Halophytes
Vegetation which is highly adapted to environment colonises the mud
which itself traps further sediment (1).
The formation/ development of Psammoseres?
SALTATION of sand particles
The grasses trap blowing sand and help to build up the dune. The
dunes in the foreground are smaller and appear to be more recently
colonised. The vegetation is more sparsely interspersed and appears
to be largely one species.
The root systems bind the sand particles together giving a more rigid structure
Compare the use of an ICZM plan and a SMP?
-ICZM- holistically- new- in the last 30 years
- SMP- hold the line, advance the line, managed retreat, do nothing
- Usually associated with a greater COST
Where are the main stores of carbon?
- 9% in sedimentary rocks in the lithosphere
- 004% in the biosphere
- 001% in the atmosphere
What has been the increase of sea levels in the UK from 1960?
Taking into consideration land subsidence and climate induced levels the total net rise as has been estimated at 25cm from 1960 upon the UK coastlines
Extra facts for Hurricane Katrina?
An “unprecedented cataclysm”
President Bush declared a state of emergency on the 27th of August
Levee system of New Orleans was only 60% complete- Scentific American coined the town a “disaster waiting to happen”
On the 7th of September 58bn was allocated from Federal Funds
Extra facts for the 2009, Victoria Bushfires?
Highest death toll in the countries history 173 EUCALYPTUS forests 40 degrees and low humidity 1,500 farm buildings 450,000 ha burnt 4 million tonnes released
AFTER 2009 created a new warning system from the Bureau of Meteorology- FDI= “Fire Damage Index”
Extra facts for the 2010, E15 eruption?
Lies West from it’s neighbour volcano Katla
Iceland= 35 active volcanoes
Airlines closed= lost 130 million dollars= largest shit down since WW2
What are the secondary impacts of volcanoes?
LAHARS- Armero tragedy- Nevada Rel Ruiz- 1985
23,000 dead
TIDAL WAVE/ TSUNAMI- meets up to 15 metres
