Climate Change in the Arctic
Though the effects of global climate change are very difficult to predict, most studies suggest that the Arctic, as a whole, will warm more than the global mean. In fact, the evidence is already mounting: glacial melting, declining sea ice, warming landmasses, decreasing ocean salinity, rising sea levels, and changes in Arctic and North Atlantic air and ocean circulation have all been observed. 20th century data has shown a warming trend of as much as 5 C over extensive land areas in the region; since the 1950s there has been a significant decrease in summer sea ice extent; and new areas of extensive permafrost thawing have developed.
The polar environment is highly sensitive to changes in temperature and precipitation patterns with significant implications for Arctic plants, animals, and inhabitants. Impacts can occur on many scales: from Arctic ice algae and other microorganisms, to walrus and polar bear populations and to Arctic human inhabitants, such as the Inuit.
General: all groups have the same questions:
1. Compare the terms ecosystem, community, species, and population as they relate to ecology.
2. What is the difference between exponential and logistic growth? What are some density-dependent factors that keep populations from growing exponentially indefinitely? What are some density-independent factors?
3. What is an ecological niche? What happens when two species have identical niches? How does the fundamental niche differ from the realized niche?
4. Explain an example of resource partitioning, and explain how natural selection can lead to character displacement.
5. Describe an example of each of the three types of symbiosis discussed in your text.
6. Explain how energy moves through the living components of an ecosystem (starting with primary productivity and including a discussion of food webs and ecological pyramids).
7. Explain how water, carbon, and nitrogen cycle through ecosystems, and give at least one example for each of how human activities can alter the cycle.
8. Seven different biomes are described in your textbook. If you were in charge of global ecosystem conservation but were told you had to focus all of your resources on preserving two of the seven types of biospheres, which would you choose, and why?
Specific to this case study
1. Give an overview of species diversity in the Artic. Compare the species diversity in the Arctic with that of the tropics. What are two hypotheses explaining this difference? (There are many more than that out there).2. Describe the history of human interactions with arctic ecosystems. Compare Inuit attitudes and habitat impacts relative to those demonstrated by non-Inuits.3. Explain three threats to biodiversity that are important in the Arctic – donŐt include global warming, but if the threats you include might work synergistically with climate change, explain these interactions.4. Describe one terrestrial and one marine food web that are characteristic of arctic ecosystems.
5. How could the changes associated with global warming impact the dynamics of these webs?
6. Consider the Polar Bear:
7. Explain at least two large-scale ecosystem changes associated to global warming that could have major impacts on overall global biodiversity.