7.1 - Energy Choices and Security

• Fossil fuels contribute to the majority of human energy supply and these vary widely in the impacts of their production and emissions and their use if unexpected to increase tp met global energy demand

  • Fossil fuels are formed through a natural process, such as in anaerobic decomposition (buried dead animals) which contains energy

  • The formation of fossils has been advantageous in terms of technological advances such as extraction of fossil fuels and inspired better transportation advances and industry development. However, as fossil fuels have largely contributed to industrialisation, that lead to a huge negative environmental burden in the form of pollution. This results in harmful greenhouse gases, acid rain, and global climate change

    • Fossil fuels are stored as solar energy

• Fossils fuels contribute to the majority of humankind’s energy supply, and they differentiate in their impacts of production and their emissions, which is expected to meet global energy demands

  • Per capita energy use in MEDC’s is much higher than LEDC’s due to higher usage of energy, fossil fuels, and technology

• Sources of energy with lower carbon dioxide emissions than fossil fuels include renewable energy ( such as biomass, solar, hydropower, wind, wave, tidal, and geothermal) and their use is unexpected to increase

  • Fossil fuels are non-renewable, as they cannot be naturally retrieved at the same rate in which it is being used up. Renewable energy is able to reduce greenhouse gas emissions, as when renewable energy sources are used, demand for fossil fuels is reduced.

  • It is important to note that non-biomass renewable energy sources do not emit greenhouse gases

• Renewable energy: energy which can be gathered from natural sources which is able to be replenished faster than they are used

• Nuclear Power is a low carbon low emission non-renewable resources but is controversial due to radioactive waste and potential scale of any accident

  • Nuclear power does not emit any greenhouse gases, acidic gases, or any harmful gases related to the deterioration of the environment

• Energy security depends on adequate, reliable and affordable supply of energy that provides a degree of independence

  • Energy security is known as the uninterrupted availability of energy sources at an affordable price

  • Uneven distribution of energy may lead to conflict

• The energy choices adopted by a society may be influenced by availability, sustainability, scientific and technological developments, cultural attitudes and political, economic and environmental factors

  • Energy choice is known as the choice that is made a to who supplies your energy. the sustainable energy sources include wind, solar and water

  • Improvements in energy efficiencies and energy conservation can limit growth in energy demand and contribute to energy security

• Advantages and Disadvantages of Energy Sources:

  • Fossil fuels:

    • Advantages: has available technology, cheap

    • Disadvantages: not sustainable to the environment, contributes to climate change and pollution

  • Nuclear power:

    • Adv: has available technology, can produce large amounts of technology, does not emit carbon dioxide

    • Disadv: Radioactive and can remain harmful for thousands of years, huge risk of disaster, takes a long time to build

  • Hydroelectric power:

    • Adv: reliable form of energy, cheap to run once constructed

    • Disadv: Has a large effect on the environment, initial building cost is expensive

  • Tidal power:

    • Adv: renewable

    • Disadv: expensive, has a negative impact on wildlife

  • Solar Power:

    • Adv: cheap for heating homes, renewable

    • Disadv: is not always reliable to work, expensive

  • Wind power:

    • Adv: renewable, cheap once set up

    • Disadv: limited to the area it is built in, is a hazard to wildlife, dangerous for some species

  • Biofuel:

    • Adv: renewable

    • Disadv: produce emission, requires large amount of land to grow the area

  • Wastes:

    • Adv: does not deplete natural capital, already has available resources

    • Disadv: Produces carbon dioxide, harmful to the environment

7.2 - Climate Change: Causes and Impacts

• Climate describes how the atmosphere behaves over relatively long periods of time whereas weather describes the conditions in the atmosphere over a short period of time

  • Weather and climate are affected by ocean and atmospheric circulatory systems

  • Human activities are increasing levels of greenhouse gases in the atmosphere

• Human activities include:

  • Increase in the mean global temperature

  • Increases frequency and intensity of extreme weather events

  • Potential for long-term change in climate and weather patterns

  • Rise in sea level

• One location to another can vary in potential impacts of climate change as it may be perceived as either adverse or beneficial. these impacts may include changes in water availability, distribution of biomes and crop growing areas, loss of biodiversity and ecosystem services, coastal inundation, ocean acidification and damage to human health

  • Positive feedback: is a feedback that increases initial warming, positive feedback accelerates temperature rise

    • Examples: melting polar ice lowers albedo, tropical deforestation increases warming and drying, increases forest cover decreases albedo

  • Negative feedback: is a process where climate feedback decreases the severity of some initial change, negative feedback slows down temperature increase

    • Examples: increases evaporation in low altitudes due to high levels of precipitation, increase in carbon dioxide in atmosphere leads to increases plant growth

• Positive and negative feedback mechanisms are associated with climate change and may involve long time lags

• Greenhouse gases effect is normal and necessary condition for life on earth. The role of these greenhouse gases are to maintain mean global temperatures, maintain normal and necessary conditions for life, and allow short wavelengths of radiation to pass through the earth’s surface, however, they trap the longer wavelength such as infrared radiation

• Global climate models are complex and there is a degree of uncertainty regarding the accuracy of their productions

• Climate is the average weather patterns over many years for a location on earth

  • Climate change is long term change to temperatures and weather patterns, these changes can be natural or vary through variations in solar cycle

• Global warming potential (GWP): is a relative measure of how much heat a known mass of a GHG traps a number of years compared to the same mass of carbon dioxide

7.3 - Climate Change - Mitigation and Adaptation

• Mitigation: attempts to reduce the causes of climate change. It is the use of technology and substitution to reduce resource inputs an emissions per unit of output. Involves reducing the flow of heat trapping greenhouse gases into the atmosphere, either by reducing these gases, or enhancing them which accumulate and store them.

  • The goal of mitigation is to avoid significant human interference with the climate system

• Mitigation strategies to reduce GHGs:

  • Reduction of energy consumption

  • Reduce of emissions of oxides of nitrogen, and methane from agriculture geo engineering

• Mitigation strategies for carbon dioxide removal:

  • Protecting and enhancing carbon sinks through land management reduction of emissions from deforestation and forest degradation in developing countries

  • Uses biomass and fuel source

  • Enhancing carbon dioxide absorption by the oceans through fertilizers of oceans to encourage biological pump

  • Even if nitrogen can reduce future effects and maximise any positive effect

• Adaptation: attempts to manage the impacts of climate change. This involves adjusting to actual or expected future climate. The goal is to reduce our vulnerability to the harmful effects of climate change.

• Adaptive capacity varies from place to place and can be dependent on financial and technical resources. MEDCs can provide economical and technical support to LEDCs

• International efforts and conferences to address mitigation and adaptation strategies for climate change