3 a and b: Changes In The Carbon Cycle

Question 1

Sequestration

Answer 1

Removal of carbon from the atmosphere

Question 2

Flows in the carbon cycle which humans influence

Answer 2

Combustion of fossil fuels
Combustion of biomass
Photosynthesis
Decomposition

Question 3

Fossil fuel combustion

Answer 3

Increased fossil fuel combustion due to industrialisation and urbanisation
Increases atmospheric carbon
Distorting equilibrium
Releases carbon particulates and gaskets compounds e.g. methane and carbon dioxide
Lithosphere -> atmosphere

Question 4

Percentage of global energy consumption which is derived form fossil fuels (2019)

Answer 4

84%

Question 5

Annual release of CO2 by fossil fuels

Answer 5

10 billion tonnes

Question 6

Percentage of carbon emissions which are anthropogenic

Answer 6

10%

Question 7

Number of vehicles in operation globally

Answer 7

947 million passenger cars
335 million commercial vehicles

Question 8

Vehicle per person USA

Answer 8

1.3
Highest global usage due to
Urbanisation, easy access to roads, limited public transport

Question 9

Energy consumption in the UK vs global average

Answer 9

UK: 19% renewable
Global: 3% renewable
More money to invest in this technology,infrastructure and industry needed for new technology
UK: 3% oil
Global 33% oil
Lack of oil reserves and expensive transport, political - bad for environment

Question 10

Methods of carbon sequestration

Answer 10

Natural: ocean uptake, vegetation uptake
Anthropogenic: anthropogenic -induced blooms; carbon capture and storage

Question 11

Ocean carbon sink by equator

Answer 11

Higher temp, higher K.E, more CO2 exsolves from the ocean.
Greater photosynthesis but does not compensate
Max 5.5 mole-2year-1 CO2 release

Question 12

Ocean carbon sink: cool waters

Answer 12

Thermohaline circulation
Pulls carbon bellow surface, cold dense water sinks
CO2 sink but less veg
-7.5 mol m-2 year-1

Question 13

Algal blooms

Answer 13

Occur in summer due to light and insolation
Cold oceans due to more dissolves CO2
Upwelling so provide ions, inorganic matter and marine snow
Anthropogenic: iron filings help algae grow

Question 14

How carbon capture and storage works

Answer 14

Piloted in coal power station
1) CO2 is separated from other emissions
2) CO2 is compressed and transported by pipeline to storage areas
3) it is injected into porous rock dead underground where it is stored permanently

Question 15

The Drax project CCS

Answer 15

In North Yorkshire
Plans to capture 2 million tonnes of CO2 year
Transports compressed CO2 by pipe to the North Sea and stored in depleted eated natural gas reservoirs
Costs 500 000 000

Question 16

Problems with CCS

Answer 16

Large costs
Uses large amounts of energy (20% of a power plants energy is required to separate CO2 and compress it)
Requires large reservoirs with specific geological conditions porous or with an impermeable layer of rock above it)

Question 17

location of surface water globally

Answer 17

97% poles
2% salt
1% usable

Question 18

abstraction in Mexico City

Answer 18

takes 50% supply from local aquifer
sinking up to 9cm year in Mexico CIty

Question 19

spatial variation caused by abstraction

Answer 19

non-homogenous water table
isolated areas of sinking

Question 20

how abstraction works

Answer 20

sealed moisturised pump moves water up a pipe from water table due to low pressure.
water table lowers due to extraction and aquifer requires a long time to refil.

Question 21

artisan basin

Answer 21

A region where aquifer is found between two layers of impermeable rock, causing pressure