Ereii

Front 1

What is thermondynamics?

Back 1

The science concerned with the relations between heat and mechanical energy or work, and the conversion of one into the other.

Front 2

What types of systems are distinguished in thermodynamics?

Back 2

- Open system: exchanges energy and matter with its environment (E.g. individual organism)

- Closed system: exchanges energy, but no matter with its environment (E.g. Planet Earth and its atmosphere)

- Isolated system: exchanges neither energy nor matter with its environment (E.g. entire universe)

Front 3

What are the laws of thermodynamics?

Back 3

4 laws of thermodynamics:

- 1st law: energy cannot be created nor destroyed; it only converts from one form to another;

- 2nd law or "Entropy law": heat energy cannot be transferred from a body at a lower temperature to a body with a higher one without the addition of energy. All conversions of energy from one form to another are less than 100% efficient.
Only in isolated systems not in equilibrium, the entropy will tend to increase over time, approaching a maximum value at equilibrium;

- 3rd law: as temperature approaches absolute zero, the entropy of a system approaches a constant minimum;

- 0th law: if two thermodynamic systems are each in thermal equilibrium with a third, then they are in thermal equilibrium with each other.

Front 4

What is "entropy"?

Back 4

- It is the core idea behind the second and third laws of thermodynamics.

- It is a measure of unavailable energy: all energy conversions increase the entropy of an isolated system.

- E.g. Fossil fuel combustion is irreversible and implies a continuous increase of the entropy of the system.
(N.B: Environment is a closed, not an isolated system)

Front 5

What could be the measures against entropy?

Back 5

- Recycling
- Increase use of extraterrestrial energy
- R&D for renewable resources and technologies
- etc.

Front 6

What are the limits of recycling as a measure to reduce entropy?

Back 6

- Not realistic
- 4th law of thermodynamics is about the complete recycling of matter, and its validity has been denied
- Complete recycling is possible, but requires more energy ==> increase of entropy = unsustainable

Front 7

What are the ecenomic implications of entropy?

Back 7

- Nothing can be produced without energy and matter transformation
- Economic activities represent one-way processes, not cyclical ones
- Entropy represents absolute scarcity, not relative scarcity: substitution might be a solution
- Sustainable growth is only possible if consumption of energy and matter stays within the limit determined by the recycling potential (depends on solar radiation)

Front 8

What are the elements of the materials balance model of economy-environment interactions?

Back 8

- Environment = sum of firms and households residuals (waste)
- Environmental firms (farms; mines; fishing forms; etc.) = sum ofproducts provided to households and non-env. firms + residuals to the environment
- Non-environmental firms
- Households
?????

Front 9

What are the implications of the materials balance model of economy-environment interactions?

Back 9

- The overall mass of matter always remains the same in the environment: NO accumulation of mass
- The economy only transforms the matter; it does not change its mass
- The mass of matter flows from the environment, and returns back to it in a differet form through the residuals' discharge from households, env. firms and non-env. firms
- The extent of recycling of households, env. firms and non-env. firms matters: recycling never restores the resource fully, BUT decreases primary resource extraction pace

Front 10

What is the difference between "stability" and "resilience"?

Back 10

- Stability: propensity of a population to return to some kind of equilibrium after a disturbance
- Resilience: propensity of an ecosystem to retain its functional and organisational structure following a disturbance
==> A resilient ecosystem does NOT imply that its component populations are stable!

Front 11

What is "biodiversity"?

Back 11

Number, variety and variability of all living organisms in terrestrial, marine and other aquatic ecosystems and the ecological complexes of which they are part.

Front 12

What are the elements of biodiversity?

Back 12

- Population: genetic diversity within the populations that constitute a species is important as it affects evolutionary and adaptive potential of the species ==> Biodiversity can be measured in terms of populations;
- Species: species' biodiversity depends on their number, the extent to which they are endemic, and their diversity ==> Biodiversity is the extent to which species can adapt and grow;
- Ecosystems: diversity of the ecosystems measures biodiversity, BUT it is still difficult to measure biodiversity at this level.

Front 13

What is the "Cowboy economy" versus the "Spaceman economy" paradigm?

Back 13

- Cowboy economy: assumes there is no limits to the outside supply (cf. environment) ==> economic success is defined in terms of GDP (flows of energy and materials transformed)
-Spaceman economy (Kenneth Boulding): assumes that Earth is a closed system, and outside supply is limited to solar energy flows. Matter and energy are only transformed by human activities, and residuals from these activities remain on Earth ==> Mankind must find her place in a perpetually reproduced ecological cycle in order to survive.

==> An appropriate measure of economic performance is to consider and manage in the long run all the available capital stocks (natural, man-made, human and social).

Front 14

What are the limits to growth?

Back 14

- Neoclassical economics:
*Environment is part of the macroeconomy
*There are no opportunity costs related to economic growth (excl. externalities)
*Default rule is the "grow forever rule": neglects the opportunity costs and the optimal scale problem
- Ecological economics:
*Macroeconomy is a subsystem of the Earth system, which is finite materially closed (only solar energy)
*Economic growth comes with opportunity costs
*if externalities are included, marginal costs of economic growth can be higher than marginal benefits = UNECONOMIC GROWTH
*Understands the importance of "when to stop [producing] rule", especially when it comes to growing economies