geography-coasts, water and carbon cycle

How much carbon did the Amazon absorb in 1990 compared to 2015

1990-2billion tonnes

2015-1billion tonnes

Tropical rainforests cover how much of earths surface?

6%

Tropical rainforests account for how much of the global photosynthesis?

30-50%

In the last 50 years how much of the primary forests have been removed and what was the land used for?

17% of primary forests were removed

Clearance was for cattle ranching(80%)

The Amazon produces what fraction of its own precipitation?

1/3 from the Amazon

2/3 from the Atlantic Ocean

On average how many tonnes of co2 does the Amazon emit?

1.9billion-decomposition and photosynthesis

What are the six stages of coastal succession?

Migration, colonisation, establishment, competition, stabilisation, climax.

What are the requirements for a sand dune to form?

-large supply of sand

-strong winds to transfer sand

-an obstacle to trap the sand

What are the land use categories and the percentages involved?

Agriculture-35-40%

Natural habitats-30-35%

Urban areas-15-20%

Forest and woodland-5-10%

Industry(+ports)-5-10%

Recreational-2-5%

What is the CBA

Cost benefit analysis: getting the best possible benefit from an investment

During interglacial periods sea levels were how much higher/lower?

130,000 years ago sea levels were 8m higher than they are today.

What is the steric effect ?

Refers to the thermal expansion/ contraction of water.

What is the difference between isostatic movement and eustatic movement?

Isostatic-change in height of land level

Eustatic-change in height of sea level

What was the Bangladesh ICZM and when was it founded?

Integrated coastal zone management- founded in (2005)

What are some examples of management on the coast of Bangladesh?

2000+ storm shelters

1500 raised mounds-protect livestock

5000km+ of embankments(123 b—d—)

148000 hectares of afforestation

What country’s are Bangladesh located next too?

China and India

How have mangrove forests adapted?

They have adapted to higher salt concentrations.

What are some opportunities in Banglades?

Natural resources

Tourism

Fertile land

What are some risks in Bangladesh?

Higher pop= food+water scarcity

Flooding= less fertile land

Environment vs humans

What proportion of houses don’t have access to electricity?

4/5

How long is the Bangladesh coastline?

730km

What is the population of Bangladesh and what proportion are at risk of flooding?

Total population is 171 million

60% at risk

How many villages have been lost to erosion on the holderness coastline?

30

How long is the holderness coastline?

61km(39miles)

How much was spent on groynes and revetments in Mappleton?

£2 million (for 500m)

How many people are unprotected from coastal erosion In easington.

700

What was the average coastal erosion rate on holderness?

1.8-2m (up to 10m if stormy)

How much of the holderness coastline is currently being protected by hard engineering?

11.4km

How much of the holderness coastline is eroded each year?

10km

How much did the holderness coastline retreat in 4000 years?

4km

Seawall: cost? Lifespan? +/-

Costs £5000 per m

Lifespan is 50-70 years

+ higher protection than other defences

- reflects rather than absorbing wave energy, expensive and not permanent.

Revetments: cost? Lifespan? +/-

Cost is £1200 per m

Lifespan is less than 50 yrs

+ cheap, LSD not hindered, reduce wave energy

- short lifespan, limited effectiveness in storms and its ugly.

Groynes: cost? Lifespan? +/-

Cost is £10,000 each

Lifespan is 25-40 yrs

+ reduce LSD, small repair cost, cheap

- short lifespan, increased erosion upshore.

What are the 3 types of sediment sources?

Clastic

Biogenetic

Fluvial

What is the geology of the holderness coastline?

Made up of glacial till (easily eroded)

Chalk headland at flambrough head which is more resistant.

Contrasting rock type (discordant coast)

Holderness: spurn head

Spurn head spit was formed by LSD

Acts as a natural barrier for the Humber estuary.

Periodically breached by 2013 storm surge.

What are some examples of a drift aligned beach?

Bucks mills

Chesil beach (west)

What are some examples of a awash aligned beach?

Saunton sands

Chesil beach (east)

What are the 3 types of erosion and give examples of each?

Marine: hydronic action, abrasion…

Subariel: denudational,mass movements.

Human: footpath erosion

Under low pressure what happens to the sea level?

There is a small rise.

How long is the Eden basin?

130km

What is orographic rainfall?

Where warm air hits mountains and forced to rise.

Where does the Eden basin flow through?

Cumbria

What is the catchment area of the Eden basin?

2400km squared

What is the topography of the Eden basin?

Max elevation 1000m

Steep slope gradient.

Milestone grit has low permeability, this means what?

High surface runoff

Slow percolation

Reduced lag time

What are the issues and actions in Carlisle (Eden basin).

Issues: 4500 residential properties and 1000 commercial properties affected and evacuation of 3000 people. The depth of flooding was 3.5m travelled at a velocity of 0.5-2.9m s. (75% of all property’s affected in the Eden basin).

Actions: embankments and flood walls

What are some issues and actions taken by Eden market towns (Eden basin)

Issues: high economic significance. A total of 540 properties are at risk of flooding.

Actions: aim to make vulnerable property’s flood resilient and resistive.

What are the number of properties at risk at each town in the Eden basin?

Carlile: 500+

Appleby, Penrith, Eden basin: 151-500

Eamont bridge: 50-150

Lower Eden: 25-50

What’s the difference between low pressure and high pressure.

Low pressure results in rising air, leading to cloud formation and unsettled weather such as rain and storms.

High pressure results in air sinking, leading to clear skys and stable weather.

What is dynamic equilibrium?

The balanced state of a system

What percentage of water do the oceans supply to the water cycle

90%

What is the field capacity of soil?

When the soil is 100% saturated so further precipitation will remain on the surface.

How much water is stored in the oceans and how much is fresh water?

Oceans: 96%

Fresh water: 2.5%

What is the difference between through flow and groundwater flow?

Throughflow: water that moves down slope through soil.

Groundwater flow: movement of water through porus rock.

What are the features of a drainage basin that influences a river?

Vegetation, basin shape, slope, geology

What are some human factors that influence a basin?

Urban areas, deforestation/afforestation, river management.

How many tonnes of carbon is stored in the lithosphere?

65,500 billion tonnes

Factors driving change in the carbon cycle?

Slow: weathering, sequestration, volcanic activity, diffusion

Fast: photosynthesis, respiration, other forms if sequestration.

Human factors affecting the carbon cycle?

Wildfires, hydrocarbon fuel extraction, land use changes, deforestation, farming practices.

What is radiative forcing?

The difference between incoming solar radiation and the radiation reflected back out.

Greater radiation reflectivity and increased ascension of warm air…

….leads to less precipitation.

“Vegetation breezes” occurs over clear land which warms faster….

This creates localised pressure, increasing cloud coverage leading to thunderstorms.

How much carbon is immediately released into the atmosphere from land clearance?

30-60%

How quickly is the Amazon shrinking?

-0.3% every yr since 2000

What is the ENSO

(El Nino southern oscillation)

It is a climate pattern that occurs in the tropical Pacific Ocean which significantly influences weather patterns worldwide.

What is the difference between a positive and negative feedback loop?

Positive feedback: occurs when the system acts to increase the effect of the change.

Negative feedback: occurs when the system acts to lessen the effect of the original change.

What are inputs and output of a system?

Inputs: energy or matter that enters a system which is the processed

Output: energy or matter that leave the system resulting from being processed.

How much lower were the sea levels the last ice age?

130m

How much water does the atmosphere store?

0.001%

How much ice mass is there in Antarctica?

90% of total ice mass

1.6million square km

How much of earths fresh water is stored in lake baikal(Asia) and the Great Lakes of North America?

20% in each

What is the dew point?

The temperature at which a body of air at a given atmospheric pressure becomes fully saturated.

What is a drainage basin

The catchment area of which a river system obtains its supply of water.

What are the units for discharge?

M³ s^-1 =cumecs

What is the water balance equation?

P=E+Q+(change in)S

Precipitation= evapotranspiration+ runoff+ the change in water held in storage

What is antecedent rainfall?

Rain falling on an already saturated surface so will not infaltrate.

How much of the earths carbon do oceans store?

0.4

What percentage of wildfires happen naturally without human intervention?

10%

How much of earths land is burned by wildfires?

3-4million sq km

What percentage of carbon contributes to radiative forcing?

65%