Ecology

1. Ecology Topics 5.1-5.3

2. Climate Change Topic 4.4

3. Carbon is cycled throughout the ecosystem as a result of many processes (combustion) (Fossilization)

4. Atmospheric carbon dioxide concentrations are monitored from many places around the world including Mauna Loa, Hawaii, and Cape Grim, Tasmania • Over the last 50 years the records kept at these stations have shown an increase in carbon dioxide concentrations Carbon and Global Warming

5. While it is normal to have global fluctuations in carbon dioxide levels, the increase that has been documented has been said by many scientists to be much greater than can be accounted for by normal environmental processes

6. A proposed explanation is that the greater than normal increase is due to human behaviors such as deforestation (less trees = less photosynthesis), and the burning of fossil fuels • In addition to the increase in atmospheric CO2 levels of other natural occurring ‘greenhouse gases’ such as methane have also been increasing due to human behaviors • e.g. our desire for red meat requires large populations of cattle that produce undesirable levels of methane

7. Greenhouse effect

8. These greenhouse gases retain atmospheric heat generated from solar radiation • This is normally good (after all it allowed humans to evolve and survive) but the increase in greenhouse gases has caused an increase in the amount of heat retained • This is what is commonly termed “global warming” Greenhouse gases

9. Greenhouse gases • H20 vapor – • Evap of oceans and transpiration in plants • CO2 - • Cell resp. and burning of fossil fuels • Most significant! • Methane (CH4) • Nitrous Oxide(N20)

10. The impact of a gas depends on its ability to absorb long wave radiation as well as on its concentration in the atmosphere • This increase in temperature can also affect climate patterns

11. There is a correlation between rising atmospheric concentrations of CO2 since the start of the Industrial Revolution 200 years ago and average global temperatures • Does this correlation justify what we have seen? • Climate – The weather patterns over a long period of time(average of several years) Climate Change

14. Looking at the possible effects of global warming on artic ecosystems gives us a glimpse of just how potentially catastrophic this phenomenon could be if left unchecked • Possible effects include but are not limited to: • Increased rates of decomposition of detritus previously trapped in permafrost

15. 30% acidification of oceans due to industrial revolution and release of CO2 • Dangerous for coral reefs Coral reefs and Carbon Dioxide

16. Holds that if the effects of a human induced change would be large and potentially catastrophic those responsible for the change must prove that it will not do harm before proceeding • William Clifford in his 1879 essay "The Ethics of Belief", contains the famous principle: "it is wrong always, everywhere, and for anyone, to believe anything upon insufficient evidence." The Precautionary Principle

17. Clifford’s argument is an extension of the 'Burden of proof' principle, (a viewpoint first held by the ancient Greeks and carried by the scientific community ever since) which states that substantial evidence must be provided before anything new can be believed • If you follow Clifford’s logic (which many do) it could be argued that it is wrong (immoral) to believe in climate change or the causes of climate change until there is sufficient evidence to support this view.

18. This viewpoint states that it is up to those who claim that there is climate change (due to human causes) to prove that this is the case. • Therefore, there is no need to respond to request for action to reduce human impact until that case has been proven.

19. The other commonly held viewpoint on global warming follows the logic of the precautionary principle, which suggests that the obligation actually falls on those accused of causing climate change (or enhanced greenhouse effect) to show that their actions are not causing damage. • It can be argued that if we wait until it is proven that humans are causing climate change it will be too late to reduce the impacts. • Is it better to respond now as a precaution even if in the long term it turns out that the case cannot be made to support global warming?