Water And Carbon

Question 1

What is the water cycle

Answer 1

The flow of water between land, atmosphere and oceans through methods such as precipitation, evapotranspiration, run-off and ground water flow

Question 2

What is the carbon cycle

Answer 2

Movement of carbon between atmosphere, oceans, sedimentary rocks, sea floor, soil and biomass, 99.9% of which is in sedimentary rocks. Flows between the stores include oxidation, combustion, respiration, photosynthesis and weathering

Question 3

What is a closed system

Answer 3

No transfers of energy both into and beyond the system, so the global carbon or water cycle is a closed system

Question 4

What is an open system

Answer 4

Systems that external input and output can be found, so the carbon and water cycle on a smaller scale are open systems

Question 5

Inputs, outputs and stores of the water cycle

Answer 5

Stores- oceans 97%, polar ice/glaciers 2%, aquifers 0.7%, lakes, soils, atmosphere, rivers and biosphere containing 0.3% between them.

• water vapour evaporated from oceans inputs into atmosphere, vapour transpired through leaves and plants, together known as evapotranspiration
• moisture leaves atmosphere as precipitation and condensation glaciers release water by ablation
• run-off into rivers from land, rivers flow to oceans or lakes, infiltration through soil
• infiltration through soul, water under gravity may percolate into permeable rocks or aquifers, ground water eventually becomes run-off

Question 6

Stores, inputs and outputs of carbon cycle

Answer 6

Stores- sedimentary rocks, atmosphere, oceans, fossil fuels, land plants, soil and sea floor sediment
Slow carbon cycle: carbon takes between 100-200 million years to transfer between each store, more about the transfer between the hydrosphere, lithosphere and atmosphere, most common is shellfish when they die their shells go to bottom of the ocean and in the heat, pressure and time they become carbon rich sedimentary rocks
Fast carbon cycle: 10-1000 times quicker, between life forms and the biosphere, land plants and microscopic phytoplankton key, photosynthesis they absorb CO2 from the atmosphere, respiration by plants and animals releases CO2, decomposition releases CO2

Question 7

What is transpiration

Answer 7

Diffusion of water vapour to the atmosphere from leaf pores

Question 8

How are clouds formed

Answer 8

• air warmed by contact with ground or sea rises as air rises and pressure falls it cools by expansion, known as convection
• air masses move horizontally across a cooler surface, advection
• warm air mixes with colder air

Question 9

What is interception

Answer 9

Vegetation intercepts precipitation storing it on branches, leaves and stems, moisture is then evaporated or falls to the ground, throughfall, rainwater that flows down branches or stems is called stem flow

Question 10

What happens to the ground in extended periods of rainfall

Answer 10

Soil becomes saturated and can’t store anymore water so has reached its infiltration capacity this means it becomes run-off or saturated overland flow

Question 11

Precipitation impact in carbon cycle

Answer 11

CO2 dissolves in rainwater to form weak carbonic acid

Question 12

Tundra case study basic facts

Answer 12

8 million km2 in Canada, Siberia and Alaska, negative heat balance for 9 months of the year, in winter 2 weeks no sun -40 degrees, low precipitation, lack of biodiversity and wildlife

Question 13

Water cycle in tundra

Answer 13

50-350mm of annual precipitation (low)
Small stores of water in the atmosphere low temp = low humidity
Limited transpiration from lack of vegetation
Low rates of evaporation
Permafrost acts as barrier so small amounts of infiltration
Sharp increase in river flow early summer as active layer melts
Ponds and wetlands on tundra in summer as permafrost stops drainage in winter months

Question 14

Carbon cycle in tundra

Answer 14

Contains globally 1600GT
Slow decomposition so more carbon accumulates
Carbon in tundra soil is 5 times larger
Used to be carbon sink but due to global warming becoming a carbon source

Question 15

Physical factors affecting the water cycle

Answer 15

Temperature- below freezing so water stored as ground ice in permafrost layer. In summer thawing means water flows on the surface, lots of ponds. Poor drainage as permafrost stops infiltration.
Permeability- low owing to the permafrost and the rocks which dominate the geology in arctic

Question 16

Physical factors affecting the carbon cycle

Answer 16

• Mainly stores as partly decomposed plants locked away for past 500,000 years
• low temp lack of water and sunlight limit plant growth so carbon in biomass is small and grows slowly, some compensation in summer months
• low temp and waterlogging slow decomposition and respiration and the flow of CO2 in the atmosphere

Question 17

Oil production in Alaska impact on water and carbon cycle

Answer 17

• Human activity heating up surrounding area
• dust deposition along roadsides creating darkened snow surfaces so less sunlight is absorbed
• removal of vegetation cover which would insulate the permafrost
• this causes extra loss of carbon as permafrost melts more

Question 18

Management strategies to prevent changes to the tundra environment

Answer 18

• insulated ice and gravel pads
• buildings and pipelines elevated
• refrigerated support
• more accurate technology

Question 19

Impact of fossil fuel combustion on the carbon cycle

Answer 19

Releases 10 billion tonnes of CO2 annually
280ppm to 400ppm
87% of all energy used is non renewable
oceans become more acidic as water react with the carbon to create carbonic acid so marine wildlife may diminish

Question 20

Sequestration of waste carbon (solution)

Answer 20

Combustion is the main driver of global warming so one possible solution is to catch the CO2 that is released and store it this is called carbon capture and storage

Question 21

Diurnal changes to the cycles (daily)

Answer 21

Water- Low temp at night = reduced evaporation and transpiration
Carbon- daytime CO2 from atmosphere to vegetation, opposite at night, without sunlight photosynthesis turns off

Question 22

Seasonal changes to the cycles

Answer 22

Water- evapotranspiration highest in summer months lowest in winter months, less loss of precipitation in winter months

Carbon- strong fluctuation in northern hemisphere, weaker near equator and souther hemisphere, in summer less carbon as more plants grow in summer due to the warmth leading to less carbon ppm

Question 23

Management strategies to protect the the global carbon cycle

Answer 23

Wetland restoration- 6-9% of earth surface and contain 35% of terrestrial carbon pool
Afforestation- planting trees
Agricultural practices- intensive livestock farming produces 100 million tonnes per year
International agreements- Kyoto 1997, paris agreement
Cap and trade- businesses allocate annual quotas for emissions they emit less they get carbon credits, financial penalties for those who exceed it