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Essay Instructions: What the Ozone Layer is made up of and how it contributes to the earths homeostasis...etc..what we can do to help maintain the ozone layer.. thanks

Essay Instructions: Essay Question: Many people confuse the large void in the ozone layer with global warming. Can you distinguish between the two phenomena? Explain how each process may harm living things.

Comments from professor: This one is very straightforward and well explained in the textbook. Be sure to answer all parts of the question.

Reference: Lutgen, F. K., & Tarbuck, E. J. (2011). Foundations of earth science (6th ed.). Upper Saddle River, NJ: Prentice Hall.

Chapter 11

Essay Instructions: i would like writer mmorley to write my essay. Thanks

write an essay which relates to chemistry and science of the topic to human concerns.

Topic- The importance of the ozone layer and what could happen to it?

Essay Instructions: 1. Individual Assignment: Case-In-Point Analysis

Select one Case-In-Point presented in Ch. 3??"5 of Environment.
Write a 700- to 900-word analysis of the selected case. In your analysis, include the following:

o Identify any unintended consequences of humankind’s activities that have led to environmental problems.
o Describe how scientific or technological activities are exacerbating or improving the existing situation.
o Discuss how a proper application of the scientific method could have helped the problem.
o Address any alternative solutions beyond the scientific method.
• Format your analysis consistent with APA guidelines.

• Flow of Energy Through Ecosystems 59
o
• C ASE IN POINT
o
• HOW HUMANS HAVE AFFECTED THE ANTARCTIC FOOD WEB
o
• Although the icy waters around Antarctica may seem an inhospitable environment, a
• complex food web is found there. The base of the food web consists of microscopic,
• photosynthetic algae present in vast numbers in the well-lit, nutrient-rich water. A huge
• population of herbivores??"tiny shrimplike krill??"eat these marine algae (Figure 3.11).
• Krill, in turn, support a variety of larger animals. A major consumer of krill is the baleen
• whale, which filters krill out of the frigid water. Baleen whales include blue whales,
• humpback whales, and right whales. Squid and fishes also consume krill in great quantities.
• These, in turn, are eaten by other carnivores: toothed whales such as the sperm
• whale, elephant seals and leopard seals, king penguins and emperor penguins, and birds
• such as the albatross and the petrel.
• Humans have had an impact on the Antarctic food web as they have had on most
• other ecosystems. Before the advent of whaling, baleen whales consumed huge quantities
• of krill. Until a global ban on hunting large whales was enacted in 1986, whaling
• steadily reduced the number of large baleen whales in Antarctic waters. As a result
• of fewer whales eating krill, more krill became available for
• other krill-eating animals, whose populations increased.
• Now that commercial whaling is regulated, it is hoped that
• the number of large baleen whales will slowly increase, and that
• appears to be the case for some species. However, the populations
• of most baleen whales in the Southern Hemisphere are still
• a fraction of their pre-whaling levels. It is not known whether
• baleen whales will return to their former position of dominance
• in terms of krill consumption in the food web. Biologists will
• monitor changes in the Antarctic food web as the whale populations
• recover.
• Thinning of the ozone layer in the stratospheric region of the
• atmosphere over Antarctica has the potential to cause long-term
• effects on the entire Antarctic food web. Ozone thinning allows
• more of the sun’s ultraviolet radiation to penetrate to Earth’s surface.
• Ultraviolet radiation contains more energy than visible light
• and can break the chemical bonds of some biologically important molecules, such as
• deoxyribonucleic acid (DNA). Scientists are concerned that ozone thinning over Antarctica
• may damage the algae that form the base of the food web in the Southern Ocean. Increased
• ultraviolet radiation is penetrating the surface waters around Antarctica, and algal productivity
• has declined, probably as a result of increased exposure to ultraviolet radiation.
• (The problem of stratospheric ozone depletion is discussed in detail in Chapter 20.)
• Another human-induced change that may be responsible for declines in certain
• Antarctic populations is global climate change. As the water has warmed in recent
• decades around Antarctica, less pack ice has formed during winter months. Large
• numbers of marine algae are found in and around the pack ice, providing a critical
• supply of food for the krill, which reproduce in the area. Years with below-average pack
• ice cover mean fewer algae, which mean fewer krill reproducing. Scientists have demonstrated
• that low krill abundance coincides with unsuccessful breeding seasons for penguins
• and fur seals, which struggle to find food during warmer winters. Scientists are
• concerned that climate change will continue to decrease the amount of pack ice, which
• will reverberate through the food web. (Global climate change, including the effect on
• Adélie penguins in Antarctica, is discussed in Chapter 21.)
• To complicate matters, some commercial fishermen have started to harvest krill
• to make fishmeal for aquaculture industries (discussed in Chapter 19). Scientists worry
• that the human harvest of krill may endanger the many marine animals that depend
• on krill for food. ?