lecture 26- dimensions of human response to environmental challenges Flashcards
Explain the pressure of energy and CO2.
Abundant and affordable energy available on demand is vital to human welfare.
Most of the needed energy comes from fossil fuels that release CO2, as only fossil fuels are currently capable of meeting the world’s baseload requirement.
What emissions are required to stabilize CO2 at a specific concentration?
This allows us to see what targets must be reached in order to stabilize atmospheric CO2.
What we find is that a reduction of >90% of emissions is needed for any kind of stabilization.
What is the Kaya Identity?
A convenient way to look at carbon emissions from energy use and to study our ability to reduce them is to use the Kaya Identity.
Different solutions focus on different terms of
the Kaya identity.
Explain the population in the kaya identity.
In the next few decades, population is expected to increase by about
0.8%/yr.
Explain Output/Population in the kaya identity.
Y/P: Per capita income (and consumption).
Historically it increases by 2%/yr in inflation-adjusted dollars (capitalism in action: the more efficient or productive wins and is rewarded by the increased wealth that can be used to buy the more things we can produce).
Explain Energy/output in the kaya identity.
E/Y: Energy intensity, or amount of energy required to generate a unit wealth.
Explain carbon/fossil fuels in the kaya identity.
C/FF: Carbon emitted per fossil fuel burned. This has been historically reduced by 0.3%/yr as we switched from coal to oil, and now to natural gas which emits less CO2 per energy produced.
Explain fossil fuels/energy in the kaya identity.
FF/E: Fossil fuels used per unit energy produced.
Explain the solution to the population problem in the kaya identity.
Population control: Difficult issue that clashes with many values, religions, and local realities.
For example, in many developing countries, having many children is what provides a “social net” to aging parents. The best proven population control mean is… increased education and wealth!
Explain the solution to the output/population problem in the kaya identity.
Reduce standard of living: Hard to achieve in countries with a higher standard of living, and not compatible with the aspirations of people in poorer (or even richer!) countries.
Explain the solution to the energy/output problem in the kaya identity.
Energy efficiency and conservation:
- Improve efficiency in energy production and in energy use;
- Reduction in consumption and/or buying goods or services requiring less energy to produce.
- Some possibilities here especially in transportation and utilities, but a long-term sustained increase in efficiency back to and beyond 1.5%/yr will require a lot of work.
Explain the solution to the carbon/fossil fuels and the fossil fuels/energy problem in the kaya identity.
Alternative energies and emissions control are simpler social choices, but many technical challenges must be (and are being) solved.
What are the technical approaches to climate change?
- Reduce emissions at the source;
- Compensate for the warming or stimulate natural processes of sinks (geoengineering)
What are examples of geoengineering approaches?
1- Solar Radiation Management: Aims to reflect a small proportion of the Sun’s energy back into space.
2- Carbon Dioxide Removal: Devise ways to accelerate sinks of CO2.
