Review Topic 3.2-3.3

1. Review Topic 3.2-3.3

2. Stockholm Agreement and Kyoto • Stockholm: • http://www.unep.org/Documents.Multilingual/Default.asp?documentid=97&articleid=1503 • Kyoto Agreement, key points • Kyoto is a legally binding agreement between signed-up countries to meet emissions reduction targets of all greenhouse gases by 2012 relative to 1990 levels. No. of countries which took part in the discussions (in 1997): 141 • No. of (industrialised) countries which ratified the agreement (in 2001): 34 • Reason for delay: the agreement needed countries responsible for 55% of 1990 emissions to ratify - after the USA refused in 2001, Russian ratification was needed - this was only obtained in Nov'04. • Overall average emissions target: 5.4% • UK target: 12.5% • Some eco-advanced countries have agreed to high emissions targets; e.g. Germany and Denmark 21% • Some less advanced countries are allowed to increase emissions: e.g. Greece +25%, Spain +15%, Ireland +13% • The large developing countries, especially China, India and Brazil, took part in the discussions but were not expected to have reduction targets. • Penalties: (in Europe) 40 Euros per tonne of greenhouse gas. Also, after 2012, shortfalls to be added to any new target and multiplied by 1.3. • Review: annual meetings; next: Montreal, late Nov '05. • Market-based approach: to give incentives through carbon trading; e.g. a company or country finding it expensive to achieve an emissions reduction has the alternative of paying money ("buying credits") so that the money can be used elsewhere on projects where an equivalent emissions reduction can be achieved at less cost. Conversely, a company or country exceeding its target receives money ("selling credits"). In Europe, carbon is being traded at around £10 per tonne. • Sceptics say that Kyoto involves a lot of expense to achieve small emissions reductions - probably true but it was at least a first international agreement to try to reduce carbon emissions after much prevarication. We must hope that agreement for more effective emissions reductions will soon be reached.

3. SY • The sustainable yield of natural capital is the ecological yield that can be extracted without reducing the base of capital itself, i.e. the surplus required to maintain ecosystem services at the same or increasing level over time. This yield usually varies over time with the needs of the ecosystem to maintain itself, e.g. a forest that has recently suffered a blight or flooding or fire will require more of its own ecological yield to sustain and re-establish a mature forest. While doing so, the sustainable yield may be much less.

4. MSY • In population ecology and economics, maximum sustainable yield or MSY is, theoretically, the largest yield/catch that can be taken from a species' stock over an indefinite period. Under the assumption of logistic growth, the MSY will be exactly at half the carrying capacity of a species, as this is the stage at when population growth is highest. The maximum sustainable yield is usually higher than the optimum sustainable yield.

5. MSY Carrying Capacity MSY This logistic model of growth is produced by a population introduced to a new habitat or with very poor numbers going through a lag phase of slow growth at first. Once it reaches a foothold population it will go through a rapid growth rate that will start to level off once the species approaches carrying capacity. The idea of maximum sustained yield is to decrease population density to the point of highest growth rate possible. This changes the number of the population, but the new number can be maintained indefinitely, ideally.

6. Energy Sources • Renewables are sustainable because they do NOT deplete natural capital. • Non-renewables cannot be replaced as fast as they are consumed. • Nuclear is NON-renewable.

7. Disadvantages to Turbines for energy production: Inefficiency • Remember efficiency is the amount of energy you get out of a fuel/. • Turbines that require steam loose energy to the environment and so are very inefficient (Only 40% of the energy is usable).

8. Disadvantages to Fossil fuels:Climate change and Unsustainable • CO2 production • Acid Rain and other air pollution • Limited supply • Once gone, GONE

9. Nuclear Power Advantages • No CO2 • Technology is available • Large amount of energy produced • Very efficient (20,000 more energy per kilo than coal) Disadvantages • Waste disposal • Melt downs • Uranium is scarce and non-renewable • Takes 20-30 years to build a power plant.

10. Renewables Advantages • Renewable • No CO2 • Small ecological footprint Disadvantages • Expensive to exploit • Politics (ex wind farms are not wanted by neighbors).

11. Examples:Hydoelectric Advantages • Cheap • Plentiful • Create lakes for recreation Disadvantages • Flooding causing habitat loss, farmland destruction and displacement of people • Disruption of river flows: • Sediment buildup up stream, loss downstream • Erosion downstream • Damage to fisheries • Dams are expensive

12. Examples:Tidal Power Advantages • Use natural tidal movements to create power Disadvantages • Need the right tides • Need the right shoreline • May interfere with navigation • May interfere with wildlife

13. Examples: Solar Advantages Two types: passive is very inexpensive for heating water (heat, showers, etc) Disadvantages Currently more expensive than fossil fuels but price is coming down. Seasonal

14. Examples: Wind Advantages • Relatively inexpensive • No Pollution! Disadvantages • Requires wind! (duh!) • Some people find them ugly • Disturb birds.

15. Examples: Biofuel Advantages Replenishable Disadvantages Still produce emissions and pollutants (but some consider this as part of the carbon cycle, not extra) Use land which could be used for food production Makes food expensive Causes destruction of habitats (ex: Rainforest) to create fields.

16. Example: Burning wastes Advantages • Use material that would otherwise not be used • Does not deplete natural capital Disadvantages • Produces Methane and CO2—BUT can be argued that so do decomposing wastes. • Removes wastes.

17. One more example: Geo thermal • http://www.youtube.com/watch?v=uVDBRQvBVso • (read case study on p. 118 so you can discuss a “named ecosystem”)

18. LEDC’s vs MEDC’s • LEDC’s use a lot of BIOFUEL –particularly wood. • MEDC’s use Fossil Fuels. • Culture and tradition favor fossil fuels Ecocentric vs. Technocentric Eccocentric favor the reduction in use of ALL fuels. Technocentric favor technologic solutions to permit the use of fossil fuels. Remember that the value of resources changes with time. If oil gets scarce, its value will diminish over time.