5.2b Greenhouse Effect
06/05/2013 § Leave a comment
Today we’re just going to keep talking about global warming as a continuation of the greenhouse effect topic. Global warming has had an impact on many of earth’s habitats, or the environment in which a species normally lives or the location of a living organism. I guess we could say it’s technically just where an animal lives.
There are numerous consequences of global warming, and a lot of them affect the environment where many animals live. Glaciers, for example, obviously melt with the increased temperature, which will greatly reduce the size of the Arctic. It’s expected that the ice caps will disappear completely at this rate. Other than the disappearing polar ice caps, polar bears and other animals who live on the ice will most definitely lose their habitat and die off. The ice-turned-water will cause sea levels to rise, as well as some flooding if there’s enough melted ice. The change in temperature of the water could also do something to affect the marine animals living in the oceans. The movement of animals in response to the melting ice could also trigger a shift in the food chain they’d been previously living and would alter almost the entire ecosystem. Also, the melting of permafrost during the summer would increase the rates of decomposition of trapped organic matter, which in turn means the release of carbon dioxide, adding into the atmosphere.
The precautionary principle is a way the government and leaders of a nation (?) handle claims and theories that have to do with any potential scientific threats. Rather then what would normally happen (prove that something is guilty of doing … something), scientists are instructed to prove that something won’t do harm before following through. For example, when people became more aware of the possibility that the production of CO2 was causing global warming, the people who needed to continue CO2 production had to follow the precautionary principle to prove that more CO2 production (or whatever action they needed to take) wouldn’t cause harm.
- Outline what is meant by the trophic level of an organism with three examples from one named habitat. (4 max)
- Compare the ways in which autotrophic, heterotrophic and saprotrophic organisms obtain energy. (6 max)
- Draw a labelled sigmoid population growth curve. 4 marks
- Explain the factors that cause a population to follow the sigmoid ( S-shaped) growth curve. (8 max)
- Apply the concept of carrying capacity to the struggle for survival resulting from overproduction of offspring. (5 max)
- Outline the international system used for naming species of living organisms. (4 max)
- Discuss the definition of the term species. (8 max)
- Name the levels and the specific taxa in the hierachy of classification using humans as an example. (2 max)
- Describe the relationship between the rise in the concentration of atmospheric carbon dioxide and the enhanced greenhouse effect. 5 marks
- Outline the consequences of a global temperature rise on arctic ecosystems. 6 marks
- Outline the precautionary principle. 5 marks
- Outline the structural differences which characterize bryophytes, filicinophytes, coniferophytes and angiospermophytes. 9 marks
- List the structural differences between bryophytes and angiospermophytes. 5 marks
- Briefly explain Darwin`s theory of evolution. 4 marks
- Outline five types of evidence which support the theory of evolution by natural selection. 6 marks
- Outline one modern example of observed evolution by natural selection. 2 marks
- Explain the evidence from homologous anatomical structures that supports the theory of evolution. 6 marks
- Outline how antibiotic resistance in bacteria can arise in response to environmental change. 5 marks
- Antibiotic resistance in bacteria is an example of evolution in response to environmental change. Using another example, explain how an environmental change can lead to evolution. 8 marks
DATA BASED QUESTIONS
Page 190, uncertainty in temperature rise projections
1. Identify the code for the least optimistic emissions scenario. —> AIFI
2. State the minimum and maximum forecasts for average global temperature change. —> min: 1.2°, max: 6°
3. Calculate the difference between the A2 and B2 forecasts of global average temperature rise. —> 3.8 – 2.5 = 1.3°
4. Compare the forecasts for arctic temperatures with those for global average temperatures. —> Both A2 and B2 increase the same way they do in the global average temperatures and arctic temperatures. A2 always increases exponentially, first steadily for the first 40 years and then increasing at a faster rate from there. B2 always seems to be constant in both graphs (constant rate of growth). The temperature in figure 12 (arctic temperature) is a little higher than all the temperatures presented in figure 11 (global average temperatures).
5. Suggest uncertainties, apart from greenhouse gas emissions, which affect forecasts for average global temperatures over the next 100 years. —> The temperature wasn’t taken at the exact same time every day, nor was it taken every day (maybe they missed a few days in a year). Rainfall also makes the temperature slightly colder. Also, an environment might have tar roads or soil roads, and tar roads absorb heat better than soil or dirt.
6. Discuss how much more confident we can be in forecasts based on data from a number of different research centers, rather than one. —> Data from only one research center isn’t sufficient information to be confident in our forecasts of the weather. The research center can only take the temperature data of so many areas, and there are other continents to cover, some areas being very difficult to reach. Data from a number of different research centers gets us a more sufficient sample size of data, with information from all over the world.
7. Discuss whether the uncertainty in temperature forecasts justifies action or inaction. —> Despite the uncertainty in the temperature forecasts, the increase is clear for a solid 100 – 110 years. Even if there is an uncertainty, we could even do a 95%CI error bar test and not all of the bars would overlap, I’m assuming, mostly because the scientists that took the data are professionals and should know what they’re doing. The data therefore justifies action, because there’s clear proof that the temperature has been increasing.
8. Discuss whether it is possible to balance environmental risks with socio-economic and livelihood risks or do priorities need to be established. —> It could be possible but it would be incredibly difficult and would also mean giving up many things that we wouldn’t want to give up. We could give up meat, for example, to reduce the use of water as well as necessity for cows and other livestock (also reducing methane production? Or is that a myth?) as well as keep ourselves healthy, overall helping the environment, but are we really going to give up beef? In a sense like this, it could be possible to have a balance, but not without making certain sacrifices and difficult decisions.