elss sg6

Question 1

the ways in which the water and cabron cycle are interdependent in the atmosphere

Answer 1

• amount of CO2 in atmosphere which affects evaporation rates and amount of water vapour in atmosphere, can cerate a PFL or NFL.
• Carbon combines with water in atmosphere, allowing chemical weathering which removes CO2 from the stmosphere. One type of chemical weathering is cabonation.
• water is needed for plants to grow and photosynthesize,photosynthesis removes CO2 from the atmosphere and stores it in the biomass.
• water is needed for the survival of all living ogrnisms an os rspiration would not happen withou it.
• water is needed for CO2 to be exhanged through the atmosphere and ocean

Question 2

ways in which cycles are interdependent via soil, cryosphere and oceans

Answer 2

soil:
- water balnce has knock on effects for wter and carbon stores between the vegeation and soi. Water deficit = dry soils, less photosynthesis.
- amount of water in soil affects the dcomposition rate or organis matter and amount of soil respiration. Wet soil = slow rates of decomposition.
cryosphere:
- higher tempuratures = reduction of water stored as ice = low albedo,flows of water increase = increased rates ofoxidation and decomposition = more atmospheric CO2, repeats
oceans:
- tempurature rise= warmer waters in the ocean are less able to absorb CO2 = less CO2 is removed from the atmosphere via diffusion and photosynthesis = temps rise

Question 3

how human activties cause changes in the availiability of water and carbon

Answer 3

1 - deforestation: clearance of forests = less abve and below ground stores. Ploughing increases soil moisture loss,inteception, ET are lower = overland flow
2 - fossil fuel burning: accounts for 87% og global primary energy consumption, removes CO2 from geological stores, causes flows of CO2 into atmosphere.
3 - ubranisation: replaces wood/farmland with buildings= less plants = less photosynthesis and store. Tarmac and roads are impermeable = more overland flow and flooding.
5 - water extraction: this has created many water shortages e.g. Aral Sea and Thames artisian Basin

Question 4

global management 1 (carbon)

Answer 4

• Kyoto 1997: 175 countries signed, reduce mean annual greehouse emissions to 5% below 1990 levels by 2012. The ountries collective emission was reduced by 2 gigatons, exceeding their target of 1GT. BUt USA, LDCs and EDCs such as China and India were exempt.
• Paris treaty 2015: 95 countries signed, agreed to keep global warming below 2C. It involved developing nations this time. BUt global temps are forecast to rise to 2.7C, each participating country sets their own GGE target, this is voluntary and not legally binding.
• CAP & TRADE: carbon trading. Cap isgovernemtns setting annual lmits/quotas on emissions. Businesses that emit less than their quota recieve carbon cradits which they can exchange for cash. Businesses that exceed must: pay a fine, invest in new technology e.g. carbon capture, carbon offset, or buy credits.

Question 5

global management strategies 2 (water and carbon)

Answer 5

carbon:
- wetland restoration: RAMSAR convention: international ocnvention on wetlands, signed in 1971,ramsar has 168 member countries and >2100 designated sites and 208 million ha of wetland. Wetlands can sequester carbon for millenia. BUT wetland restorations need to be on a larger scale which isnt likely due to pressures from population growth.
water and carbon:
- Afforestation: 15% f global CO2 emissions are caused by deforestation. Afforestation involves planting trees in deforested areas or in areas never been forested. successes; plantatoins grow fast, tree canopies can intercept so less risk of flooding, trees are carbon sinks and are a good carbon store. BUT high costs of afforestation mean it is often done small scale, can be a long process.

Question 6

global management strategies 3 (water)

Answer 6

• imporving water allocation: uneven distribution of water menas by 2025 2 billion could experience water shortages. Strategies: domestic use: managing dailt use, shorter showers, storing rainwater. Agricultural use: cut down livestock farming, use plants that require less water, contour plowing= drip irrigation. Industrial use: build dams, use treated waste water for industry, use desalinisation.
• Drainage basin planning: Helsinki rules 1966: asserted rights of all bordering nations to have an equitable share in water rsources from cross water rivers. Successes: International treaties provide guidance on how states can achieve consensus, it was necessary due to lots of major rivers crossing boundaries. But: treaties are non-legally binding and it is difficult for an equitable share of water resources to be achieved.