Physical geography

Carbon cycle

Enquiry question 1: How does the carbon cycle operate to maintain planetary health?

6.2 Biological processes sequester carbon on land and in the oceans on shorter timescales

6.2A - Oceanic Sequestering

Biological sequestering occurs on significantly shorter timeframes, ranging from hours to centuries, than geological sequestering.

The oceans are the second biggest carbon storage system on the planet. The marine carbon storage is 50 times higher than the atmosphere's. The majority of the oceanic crust is held in the form of marine algae, plants, and coral. The remainder exists in dissolved form.

Physical pumps:

1. Downwelling and upwelling currents transport carbon compounds to various sections of the ocean

2. Downwelling takes place in areas of the ocean when colder, denser water lowers

3. These currents carry dissolved carbon dioxide down to the deep ocean

4. Once there, it is carried by slow-moving deep ocean currents for hundreds of years

5. These deep ocean currents, which are part of the thermohaline circulation, eventually return to the surface via upwelling

6. As the frigid deep ocean water rises to the ocean surface, part of the dissolved carbon dioxide is released back into the atmosphere

Biological pumps:

1. Through photosynthesis, they transport carbon dioxide from the ocean's surface to marine plants known as phytoplankton. Phytoplankton are tiny plants and plant-like creatures that drift or float in saltwater or freshwater, alongside diatoms, protozoa, and small crustaceans

2. Carbon dioxide is successfully converted into food for zooplantic (microscopic creatures) and their predators

3. The majority of the carbon dioxide absorbed by phytoplankton is recycled at the water's surface. Approximately 30% sinks into deeper waters before being transformed back into carbon dioxide by marine microbes

Carbonate pumps:

1. These are sediments formed by dead creatures that fall to the ocean floor, particularly the hard outer shells and skeletons of fish, crabs, and corals, which are all high in calcium carbonate

6.3 A balanced carbon cycle is important in sustaining other earth systems but is increasingly altered by human activities

6.3B - Maintaining a Balanced Carbon Cycle

A balanced carbon cycle is the result of several components operating in harmony with one another.

Photosynthesis:

Photosynthesis by terrestrial and marine organisms is critical for maintaining relatively constant carbon dioxide levels and so helping to regulate the Earth's mean temperature

The quantity of photosynthesis varies geographically, especially in relation to net primary productivity (NPP). (This is the quantity of organic matter accessible for harvesting or consumption by humans and other animals.) NPP levels are highest in warm, wet areas of the earth, notably in tropical rainforests and shallow ocean waters. The tundra and boreal woodlands have the lowest levels

Soil health:

Soil health is an important part of ecosystems and a critical component of the carbon cycle's regular operation. The quantity of organic carbon stored in the soil determines soil health. The quantity of storage is governed by the balance of the soil's inputs (plant and animal remnants, nutrients) and outputs (decomposition, erosion and uptake by plant and animal growth.)

Carbon is the most abundant component of soil organic matter, and it contributes to the soil's moisture-retention capacity, structure, and fertility. Organic carbon is concentrated in the soil's surface layer. A healthy soil contains a vast surface reservoir of accessible nutrients, which condition ecosystem production. All of this explains why even minor surface soil erosion may be so damaging to soil health and fertility

Enquiry question 2: What are the consequences for people and the environment of our increasing demand for energy?

6.4 Energy security is a key goal for countries, with most relying on fossil fuels

6.4A - The Energy Mix

Energy security is accomplished when there is a consistent supply of energy at a reasonable price on a national scale. All governments strive towards this; the most secure energy scenario is one in which the national need for energy can be met entirely by local sources. The more a country relies on imported energy, the more vulnerable it is to economic and geopolitical dangers. The following are four critical factors of energy security:

1. Availability

2. Affordability - competitively priced energy supply

3. Accessibility

4. reliability - without interruption

5. The significance of energy security arises from the fact that energy is essential to a country's operation. It, for example, powers most modes of transportation, illuminates towns, and is utilised in some types of commercial agriculture; warms/cools houses and powers household appliances; is essential to contemporary communications; and drives most forms of manufacturing

6. Energy consumption is quantified in two ways:

7. In terms of per capita use, i.e. in kilogrammes of oil equivalent or kilowatt hours per person In general, this metric grows in tandem with economic progress

By a metric called as energy intensity, which is calculated by dividing the amount of energy consumed per unit of GDP. The fewer the energy units, the more effectively a country uses its energy supply. In general, the value of energy intensity decreases as the economy grows

The energy mix is the mix of various energy sources utilised to fulfil a country's overall energy demand. It is a crucial aspect of energy security and differs by nation. There are distinctions between the following:

• Domestic and international sources

• Primary and secondary sources

Primary = found in nature, unconverted/transformed It can be renewable (water, wind, and sunshine) or nonrenewable (coal, oil, and gas).

Secondary = obtained through the alteration of original materials, typically more convenient (electricity)

6.4B - Energy Consumption

Factors influencing per capita energy use include:

• Physical accessibility

• Cost

• Living conditions

• Priorities for the environment (of governments)

For some, energy policy will be about finding the cheapest way to fulfil the country's energy demands, regardless of environmental implications. Others will aim to expand their reliance on renewable energy sources, while others will put regulations in place to promote energy efficiency and energy savings

• Climate

Consumption levels in North America, the Middle East, and Australia are quite high, reflecting the additional energy required to make extreme heat and cold more pleasant (at home, at work and in public places)

• Public perception

Some customers see energy virtually as a human right, and hence utilise it with little or no concern for the environmental implications. Others prioritise reducing energy waste while increasing security

France VS the US

The United States and France are ranked second and tenth in the league table of energy users, respectively, while France's overall energy consumption is one-tenth that of the United States. The disparity is partly explained by population differences: 318.9 million in the United States against 64.6 million in France. In terms of per capita income, the United States is first, with France ranked sixth.

Over three-quarters of energy in the United States is derived from fossil fuels. The energy balance of France is substantially different, with half of its energy coming from fossil fuels and roughly 40% coming from nuclear energy. In terms of energy security, France lags well behind the United States, owing to the fact that over half of its main energy is imported. The US is much more self-suffcient

6.4C - Energy Players

An energy pathway is the journey that any type of energy takes from its source to its point of consumption. The routes use several modes of transportation, including tanker ships, pipelines, and power transmission networks.

Energy firms and governments from energy-producing countries are at the supply end of the supply chain. On the demand side, there are governments as well as a variety of consumers ranging from industrial to domestic. Companies responsible for the movement and processing of energy can be found along the channels

TNCs

Gazprom, ExxonMobil, PetroChina, and Royal Dutch Shell are among the major players in the oil and gas industry. Nearly half of the top 20 enterprises are state-owned (in whole or in part) and hence heavily influenced by the government. As a result, they are not technically TNCs. Most are involved in a variety of operations, including exploration, extraction, transportation, refining, and production of petrochemicals

Energy Companies

Companies that transform primary energy (oil, gas, water, nuclear) into electricity and subsequently distribute it are critical here. The majority of businesses are involved in the distribution of both gas and electricity. When it comes to determining consumer pricing and tariffs, they have significant power

Organisation of the Petroleum Exporting Companies

OPEC has 14 member countries that control almost two-thirds of the world's oil reserves. As a result, it has influence over the volume of oil and gas entering the worldwide market, as well as the pricing of both commodities. OPEC has been accused of restricting output in order to raise oil and gas prices.

Consumers

Although this is a broad word, the most important customers are likely to be those in transportation, industry, and households. When it comes to determining energy pricing, consumers are mostly spectators.

Governments

They can perform a variety of functions, including guardians of national energy security and influence energy source for geopolitical purposes.

Enquiry question 3: How are the carbon and water cycles linked to the global climate system?

6.8 There are implications for human well-being from the degradation of the water and carbon cycles

6.8C - Declining Ocean Health

Changes in marine food webs are being produced by the reduction in ocean health caused by acidification and bleaching. Fish and crustacean populations, in particular, are falling and shifting distributions. Such shifts are especially noticed in underdeveloped nations.

• According to the FAO, fishing employs 500 million people, 90 percent of whom reside in poor countries

• Millions of fishing households rely on seafood for both income and nourishment

• Some affluent nations, most notably Iceland and Japan, prefer seafood as part of their diet

• Aquaculture is growing in popularity, but its productivity is being hampered by dropping PH levels and rising temperatures

Tourism is another industry that is under threat, particularly in nations such as the Caribbean, where coral reefs, which are currently deteriorating, have historically drawn scuba-diving visitors. Rising sea levels are another effect of climate change that affects tourism and its coastal infrastructure, as seen in the Maldives and Seychelles. The expenditures of bolstering coastal defences frequently surpass the financial capacity of poorer coastal countries

6.9 Further planetary warming risks largescale release of stored carbon, requiring responses from different players at different scales

6.9A - Uncertainty about the Future

There is a lot of uncertainty about the future, which generates a lot of issues, particularly:

Will the amount of GHG emissions continue to rise?

Is there a limit to the amount of GHG that may be emitted into the atmosphere?

other carbon sinks and storage' resilience—what are their capabilities, and might they store more?

How much warmer is the climate getting?

What amounts of carbon are projected to be released as a result of feedback processes like as carbon release from peatlands and thawing permafrost?

When, if ever, will the rate of population increase slow?

Will the type and rate of economic development always be carbon-based?

Will fossil fuels be totally replaced as a result of the harnessing of alternate energy sources?

Because there is still so much unknown, any predicting of global futures should be done with extreme caution. What should we do if global warming continues?

There are two possible courses of action:

Adaptation is the process of modifying our ways of life so that we can live with most, if not all, of the consequences of global warming

Staying with the situation rather than resolving it

Mitigation the reduction or prevention of GHG emissions through the development of new technologies and the use of low-carbon energy (renewables and recyclables)

Addressing the underlying source of the problem

6.9B - Adaptation Strategies

Land-use Planning

Benefits

• Soft management includes land-use zoning and development limitations in floodplains and on low-lying beaches.

• Strict runoff limits and soakaways must be enforced

Costs

• Public dislike

• Abandoning high-risk locations and relocating to safer areas is frequently impossible, especially in megacities like Dhaka, Bangladesh, or Tokyo-Yokohama

• A political "hot potato" needs strong governance, enforcement, and remuneration

Flood-Risk Management

Benefits

• Traditional hard-management techniques include localised flood defences and river dredging

• Simple improvements, such as permeable tarmac, can help to lessen flood risk.

• Reduced deforestation and increased afforestation upstream to absorb water and lessen the risk of flooding downstream

Costs and dangers

• Debate about financing sources, particularly during times of economic hardship

• Landowners may seek recompense for afforestation or 'sacrificial land' set aside for flooding

• In harsh management, such as dredging, constant maintenance is required; management failures can raise risk

• A deeply embedded culture of 'techno-centric fixes': a notion that technology cannot overcome natural processes

Water Conservation and Management

Benefits

• Fewer resources are consumed, and less groundwater is extracted.

• Attitudinal change is a long-term process: increase the usage of grey (recycled) water

Costs and risks

• Efficiency and conservation will not be able to meet the rising demand for water

• Changing cultural patterns that have a huge water footprint requires government promotion and regulation, such as smart metres

6.9C - Mitigation Strategies

The UK has the Department of Energy and Climate Change (DECC) which is responsible for mitigation policies

Carbon taxation

• The carbon price floor tax establishes a minimum price that businesses must pay to release carbon dioxide. It was controversial with both business and environmental organisations, and its impact on emissions was questionable. The policy was 'frozen' in 2015

• In 2015, lower road taxes for low-carbon-emitting vehicles were repealed.

• Oil and gas exploration tax breaks were enhanced in 2015 to boost fossil fuels, resulting in the fracking controversy

Afforestation

• Tree planting in the United Kingdom is rising, which aids in carbon sequestration. The Forestry Commission, organisations such as the National Trust and the Woodland Trust, landowners, and local governments are all involved

• The Big Tree Plant programme urges communities to plant one million new trees, most of which will be in metropolitan areas

Renewable Switching

• The level of transition from fossil fuels to renewables and nuclear power is determined by the interaction between the major energy producers and the government. Renewables produce intermittent power, but fossil fuels supply constant power, which is required for our present infrastructure

• The Climate Change Levy, enacted in 2001 to stimulate investment in and usage of renewable energy, was repealed in 2015

Carbon Capture and Storage (CCS)

• Despite its promise, there are few real geologic CCS projects across the world. The only large-scale working scheme is Canada's Boundary Dam

• The UK government cancelled full-scale projects at gas- and coal-powered facilities at Peterhead, Scotland, and Drax, Yorkshire, respectively, in 2015

Energy Efficiency

• The Green Deal initiative promoted energy-saving home renovations such as efficient boilers and lights, as well as increased insulation. It was decommissioned in 2015

• Energy suppliers must follow the Energy Company Obligation plan in order to provide energy-saving solutions to homes