Category Archives: Geology

Earth Science-Questions and Answers

Question

Question 8

Examine the graph below. In your own words, describe why we see a seasonal difference in CO2 concentration in the atmosphere.

Question 9

Compare and contrast weather and climate and how the atmosphere affects both.

Question 10

In the picture below, explain why the balloons are rising in terms of atmospheric stability. What effect does water vapor have on atmospheric stability?

  Question 11

Examine the figures below. Contrast the role the greenhouse effect plays in the atmospheres of (a) the Moon, (b) Earth, and (c) Venus.

Question 12

Many people confuse the large void in the ozone layer with global warming. Can you distinguish between the two phenomena? Discuss the causes of each. Explain how each process may harm living things. (Refer to the additional reading for this Unit).

Sample paper

Earth Science

 

Question 8

Examine the graph below. In your own words, describe why we see a seasonal difference in CO2 concentration in the atmosphere.

From the graph, it is clear that the level of carbon dioxide has been increasing at an alarming rate since the 1960s. The increase in concentration of carbon dioxide in the atmosphere reflects continued burning of fossil fuels, which contributes to accumulation of carbon dioxide in the atmosphere. The seasonal variations in the level of carbon dioxide are due to the processes of photosynthesis and respiration. During the day, plants use carbon dioxide for photosynthesis while at night they use oxygen and release carbon dioxide during respiration. However, the amount of carbon dioxide they take in is much more compared to the one released. This causes frequent variations in the level of carbon dioxide. In addition, during the warm months, plants use more carbon dioxide during photosynthesis and generally grow more. This causes fluctuations in the level of carbon dioxide in the atmosphere.

 

Question 9

 

Compare and contrast weather and climate and how the atmosphere affects both.

Weather and climate are terms often confused due to their close meaning. Weather refers to the condition of the atmosphere as measured in relatively short period of time. On the other hand, climate refers to the condition of the atmosphere at a particular place and as measured over a relatively long period of time (Barry & Chorley, 2010). The atmosphere contains various elements such as gases, dust particles, and other molecules. These are relatively constant. However, over the last century, the level of carbon dioxide has increased due to human activities. This has caused changes to the water cycle, carbon cycle, and the nitrogen cycle. Increase of greenhouse gases such as carbon dioxide has led to too much heat being trapped in the earth’s atmosphere, hence leading to global warming Barry & Chorley, 2010). This has altered the everyday weather conditions in various places, leading to extreme weather conditions such as flooding, tornadoes, and wide temperature variations. It has also affected climate by changing the average weather conditions of a place over a long period. For instance, some places are facing prolonged dry periods and hence desertification.

Barry, R. G., Chorley, R. J. (2010). Atmosphere, weather, and climate. United Kingdom, UK: Taylor & Francis.

Question 10

In the picture below, explain why the balloons are rising in terms of atmospheric stability. What effect does water vapor have on atmospheric stability?

Atmospheric stability is an assessment of the tendency of the atmosphere to encourage or discourage vertical motion of air. The balloons in the picture rise because they are filled with hot air. Hot air is less dense and tends to rise until it reaches a point where its temperature becomes even with the surrounding temperature. Parcels of hot air in the atmosphere tend to rise, which indicates that the atmosphere is unstable. This is the same for the balloons filled with hot air. The balloons are like parcels of warm air that tends to rise. Water vapor restores the atmospheric stability. When water vapor rises, it reaches the condensation point. This represents a point where the water vapor changes into liquid due to a decrease in temperature. The rising warm air thus encounters a cold front, leading to a balance between the two.

Question 11

 

Examine the figures below. Contrast the role the greenhouse effect plays in the atmospheres of (a) the Moon, (b) Earth, and (c) Venus.

The greenhouse effect plays a critical role in the atmospheres of moon, earth, and venus. The greenhouse effect refers to the earth’s ability to trap heat and maintain relatively stable temperatures with minimal fluctuations. Due to lack of greenhouse gases on the moon’s atmosphere, wide temperature fluctuations occur. During the day, temperatures can reach as high as 2300 F, while during the day temperatures can reach as low as -2900F (Kutner, 2003). The main reason for the wide temperature fluctuation is that during the night, all heat escapes back into space causing temperatures to drop. The earth’s atmosphere is made of greenhouse gases that trap heat such as methane, water vapor, carbon dioxide, CFC and other non-greenhouse gases. During the day, the earth absorbs the sun’s radiation. Much of this radiation is reradiated into space in form of heat. However, due to the presence of greenhouse gases, some of the sun’s radiation is trapped by the earth’s atmosphere. This makes the earth’s temperature to remain relatively constant during the day and night. Contrary to the above, the temperatures at venus remain extremely high even during the night. This is because venus has a thick atmosphere that is primarily made up of carbon dioxide gas, the main greenhouse gas (Kutner, 2003). As such, venus traps most of the sun’s heat and prevents it from escaping into space, causing a warming effect.

Kutner, M. L. (2003). Astronomy: A physical perspective. Cambridge: Cambridge University Press.

 

Question 12

 

Many people confuse the large void in the ozone layer with global warming. Can you distinguish between the two phenomena? Discuss the causes of each. Explain how each process may harm living things. (Refer to the additional reading for this Unit).

The large void in the ozone region represents a layer in the earth’s atmosphere around the Polar Regions where the ozone layer has undergone depletion. Depletion of the ozone layer is the result of human activities such as release of harmful gases into the atmosphere. The release of chlorofluorocarbons (CFCs) from refrigerants and aerosol spray cans is the major cause of ozone depletion (Tabin, 2008). The CFCs causes a chemical reaction with the ozone layer, causing a breakdown of the ozone layer. The ozone layer is significant because it protects living organisms from harmful radiations from the sun. The ozone layer absorbs the radiations thus preventing too much of it from reaching the living organism which may lead to skin diseases, eye damage, cancers, and other diseases.

On the other hand, global warming refers to the warming effect that is caused by accumulation of greenhouse gases into the atmosphere (Tabin, 2008). The two phenomena are similar in that they are caused by accumulation of harmful gases into the atmosphere. In both cases, human activities are the major causes. Global warming is different in that greenhouse gases cause accumulation of excess heat in the atmosphere. The role of greenhouse gases is to trap some of the sun’s heat from escaping into space. However, too much accumulation of greenhouse gases has resulted to more heat being trapped in the earth’s atmosphere, hence higher global average temperatures than normal. A major consequence of global warming is climate change.

Reference

Tabin, S. (2008). Global warming: The effects of “ozone” depletion. New Delhi: A.P.H. Pub. Corp.

discussion board question

Click here

http://climate.nasa.gov/climate_resources/42/

to watch the NASA video Temperature Puzzle. Many people are quick to dismiss global warming after a cold winter or a late summer. After watching the video, how would you respond to this person? Why is it difficult to base climate on a single season’s weather? Use data and examples to support your answer. (Note: please base your discussion on what you have learned from the video and textbook reading. This is NOT meant to be a discussion of political ideology.)

My response is that there is clear evidence linking global warming to erratic weather pattern. First, in the last decade, global average temperature has increased by about a third of degree Fahrenheit. Since the first temperature recordings in the 1880s, global average temperature has increased by over 1 degree Fahrenheit. Although the sun’s energy output fluctuates depending on solar cycle, NASA asserts that the last decade has been the warmest decade ever recorded, yet the sun has been on a deep low cycle. Climate cannot be based on a single season’s weather because there are multiple factors that affect weather in time. For instance, solar cycle, wind patterns, pressure, and other factors that affect weather in the short run.

 

Earth Science -Questions and Answers

Questions

Question 8

  1. When you are at the beach, you notice that the waves seem to “break” at the same point as they come towards shore. Explain what is happening beneath the surface to cause the waves to break at this point.

Question 9

  1. Discuss two reasons why summer temperatures in coastal locations in Southern California are cooler than coastal locations at the same latitude in Georgia.

Question 10

  1. The best place to look for crabs is between the high tide and low tide zones (the tidal flat). Knowing this, would you expect to find more crabs during a full moon/new moon or during a quarter moon stage? Explain why.

Question 11

  1. You are taking samples of water depth as you cross the ocean from North America to Africa. You notice that about halfway through your journey, the ocean floor is more elevated. Explain the plate tectonic processes that form this elevated region of the seafloor.

Sample paper

Earth Science

Question 8

Moving closer to the shoreline, the depth of the water becomes shallower. As the waves move towards the sea, they begin to slow down owing to the shallow depth of water. The wave makes contact with the bottom of the ocean as the waters become shallower. As the waves move slowly, the wavelength or period becomes shorter. This increases the wave height. As the seafloor becomes steeper, the wave height becomes more pronounced. The part of the wave near the sea floor moves slowly as the crest increases speed. The bottom of the wave moves slowly because of increased friction with the sea floor. At some point, the crest of the wave overtakes the bottom, causing the water to break at a specific depth level. Waves therefore seem to “break” at the same point due to the reducing depth of the sea floor (Lutgens, Tarbuck, & Tasa, 2016).

Reference

Lutgens, F. K., Tarbuck, E. J., & Tasa, D. G. (2016). Foundations of earth science. New York, NY: Pearson Education.

Question 9

One of the reasons why coastal locations in Southern California remain cooler is the action of ocean currents. The costal locations in Southern California are swept by the California Current, which is part of North Pacific Gyre (this comprises of a large swirling current common in the northern pacific basin) (Cropper, Hanna, & Bigg, 2014). This current causes cold waters from northern pacific to move towards the Southern California coastline, and thus a cooling effect even during summers. Another reason why the costal locations remain cooler is upwelling. Upwelling occurs when cold ocean waters rise to the surface. This is caused by Coriolis effect that creates the Ekman spiral. Ekman spiral occurs when the surface of the ocean moves away due to the Coriolis Effect, causing waters at the bottom to rise (Cropper, Hanna, & Bigg, 2014).

Reference

Cropper, T. E., Hanna, E., & Bigg, G. R. (2014). Spatial and temporal seasonal trends in coastal upwelling off Northwest Africa. Deep-Sea Research, 86(1): 94 – 111. http://dx.doi.org/10.1016/j.dsr.2014.01.007

Question 10

I would expect to find more crabs during the full moon. This is because during full moon, the gravitational effect of the moon and the sun combine to produce extreme tides. For instance, the high tides occur very high while the low tides occur very low (Beukema, Wolff, & Brouns, 1990). This means that one is likely to find more crabs during this time.

Reference

Beukema, J. J., Wolff, W. J., & Brouns, J. J. W. M. (1990). Expected Effects of Climatic Change on Marine Coastal Ecosystems. Dordrecht: Springer Netherlands.

Question 11

The elevation between North America and Africa’s ocean floor is caused by subduction of the pacific plate under the North American plate. Plates moving close to one another cause subduction (Lutgens, Tarbuck, & Tasa, 2016). When the plates meet, one plate may move underneath the other within the subduction zone. Since one plate moves above the other, the surface becomes relatively raised.

Reference

Lutgens, F. K., Tarbuck, E. J., & Tasa, D. G. (2016). Foundations of earth science. New York, NY: Pearson Education.

 

Earth Science-Questions and Answers

Earth Science

Question 1

What unlikely feature formed along the fault scarps of Central California?

The Salton Sea

Wallace Creek

Sag ponds

Pinnacle National Park

Question 2

What two plates interact to form the San Andreas Fault?

 

Pacific plate and Nazca plate

 

North American plate and Pacific plate

 

North American plate and Cocos plate

 

Pacific plate and Caribbean plate

 

Question 3

 

When was the last big Earthquake along the main fault?

 

1989

 

2011

 

1906

 

1871

 

Question 4

 

In which direction does Wallace Creeks offset?

 

Northwest

 

Southwest

 

Southeast

 

Northeast

 

Question 5

 

When did the San Andreas Fault appear?

 

28 million years ago

 

50 million years ago

 

28,000 years ago

 

50,000 years ago

 

Question 6

 

The San Andreas Fault is called a:

 

Right lateral strike slip fault

 

Transform dip-slip fault

 

Right dip-slip fault

 

Transform strike slip fault

 

Question 7

 

What is an example of this plate movement?

 

The separation of California and Baja California

 

Rocks of Pinnacles National Park match those of Antelope Valley, nearly 200 miles away

 

The northward flow of rivers along the San Andreas fault

 

The Salton Sea

 

Question 8

 

Why do mountains form around Big Bend?

 

Magma surfaces when the San Andreas Fault creeps.

 

The bend in the fault causes this area to be bound, squeezed, and uplifted.

 

The fault is raised here.

 

Fault creep creates pressure, causing uplift.

 

Question 9

In your own words, what creates Earthquakes? (75 word minimum)

Earthquakes occur in areas where there are weak fault lines underneath the earth’s surface. Tectonic plates are always moving, albeit slowly. When two plates collide, vibrations occur which travel outwards as seismic waves. This causes the ground to shake. Another way earthquakes occur is when two plates move alongside each other, but in the process become stuck due to friction. When the plates overcome the force of friction at the edges, sudden pressure release occurs, which causes vibrations that travel as seismic waves (Hung et al., 2010). The seismic waves also travel laterally as well as downwards.

Reference

Hung, C. J., National Highway Institute (U.S.), & Parsons, Brinckerhoff, Quade & Douglas.             (2010). Technical manual for design and construction of road tunnels–civil elements.       Washington, D.C.: U.S. Dept. of Transportation, Federal Highway Administration,         National Highway Institute.

ASSESSMENT

 

number nine

Recall from reading the nature of volcanoes, and in your own words, briefly discuss how the rate of cooling determines the type of rock that forms from magma/lava.

The rate of cooling significantly determines the type of rock that form from magma (Owings, 2015). When magma cools, it forms igneous rocks. The rate of cooling determines the crystal sizes of the igneous rocks. When lava flows to the surface, it cools quickly, leading to formation of small crystals. This leads to formation of obsidian and basalt rocks also known as extrusive igneous rocks. When lava cools slowly (for instance underground lava), large crystals develop. This leads to formation of igneous rocks such as gabbro and granite that comprise of large crystals.

number ten

Recall from your reading about the nature of volcanoes, and in your own words, compare and contrast aa and pahoehoe lava in appearance and how they form

Aa and pahoehoe are the major forms of basaltic lava flow. A major difference between the two is that pahoehoe appears smooth and is viscous in texture, while aa has rough surfaces. Rapid lava flows characterize aa formation, while pahoehoe is characterized by low velocity flows. Aa has higher viscosity while pahoehoe has lower viscosity (Owings, 2015).

Reference

Owings, L. (2015). Igneous rocks. Abdo Publishing.

number eleven

In your own words, briefly explain how a caldera forms from principle types of volcanos.

A caldera may form in two principle ways, which include violent volcanic eruption and from collapse of the surface rocks around a void lava chamber (Gottsmann & Martí, 2008). Violent volcanic explosions occur in magma comprising silica that is highly viscous. As the lava rises, trapped gas bubbles expand due to reduced pressure. When they reach close to the vent, a violent explosion may occur, throwing large pieces of rock away. This may leave the water table exposed or water may collect in the area. This leads to formation of a caldera. Collapse calderas occur when a magma chamber undergoes eruption and is left empty. This leaves rocks on the edges of the chamber hanging. With time, they collapse under their own weight into the chamber, forming a wide caldera.

Reference

Gottsmann, J., & Martí, J. (2008). Caldera volcanism: Analysis, modelling and response. Amsterdam: Elsevier.

number twelve  (two hundred words)

In your own words, discuss volcanic hazards. Although commonly thought to be associated with most volcanic eruptions (by the general public), lava is rarely responsible for the loss of life. Which hazards would tend to be more deadly? Finally, indicate and discuss those hazards that are a direct result of a volcanic eruption as well as those hazards that are indirectly linked. (Hint: think of “indirectly associated” hazards as “side effects”.).

There are various volcanic hazards that may impact people during eruptions. One of the volcanic hazards is debris-flow avalanches. This may occur when over steepened volcanoes collapse, causing a debris flow over the steep slopes of the mountain. The avalanches may endanger lives of those living near the eruption point. Another hazard is pyroclastic falls that comprise of tephra and other projectiles. These include debris of various sizes that are projected at great velocities (Loughlin et al., 2015). Falling debris may be dangerous to people and property. Another hazard involves the various gases that may be released during an eruption. Common gases include water vapor, fluorine, sulfur oxides, carbon monoxide, chlorine, and hydrogen sulfide. Another hazard is pyroclastic density currents that comprise of a mixture of ash, hot gases, and rock dust. These currents can move in the air at great speeds causing death and destruction.

Lahars is another common hazard around volcanoes. Lahars may occur when volcanic flows encounter water or ice (Loughlin et al., 2015. When volcanic flows mix with water or ice, they can move through valleys at higher speeds causing destruction. Direct hazards from valcanoes include gases, pyroclastic  falls, pyroclastic density currents, and lava. These can cause death and destruction directly. For instance, pyroclastic currents and falls may injure people by falling on them and causing physical harm (Loughlin et al., 2015). Indirect hazards include debris-flow avalanches, lahars, and destruction of the natural flora and fauna of the environment. This may lead to famine especially where crops are destroyed.

Reference

Loughlin, S. C., Sparks, S., Brown, S. K., Vye-Brown, C, Jenkins, S. F. (2015). Global volcanic hazards and risk. Cambrige: Cambridge University Press.

Aryana Robinson Response to “five good emperors.”

 

Briefly describe what happens at a subduction zone

Question

Briefly describe what happens at a subduction zone

Explain how an accretionary wedge forms.

How are faults, hypocenters, and epicenters related? Faults that are experiencing no active creep (relatively consistent yet minor movements) may be considered “safe”. Rebut or defend this statement with what you have learned so far about faults

Sample paper

Earth Science

Number 1

Briefly describe what happens at a subduction zone

A subduction zone is the result of meeting of the earth’s tectonic plates. The earth’s crust comprises of massive plates known as tectonic plates. These plates may move along each other or slide over each other due to tectonic forces acting on them. When tectonic plates move away from each other, they form a boundary at the point of separation. When they move towards each other, tectonic plates collide, where one sinks beneath the other plate.

Number 2

Explain how an accretionary wedge forms

An accretionary wedge occurs along the surface compressions formed by the converging plate boundaries. When the two tectonic plates meet, one of them sinks underneath the other. As one of the tectonic plates undergoes subduction, loose sediment from the plate is scrapped off (Christiansen, 2014). The loose sediment forms the accretionary wedge after it piles up near the point of subduction. Folds may develop along the accretionary wedge. As more sediment is removed from the sinking tectonic plate, the wedge or mass of loose sediments grows towards the trench formed from the sinking plate (Christiansen, 2014). With time, the accretionary wedge collapses towards the trench. This results to the formation of the accretionary wedge, which is looks deformed in shape.

Reference

Christiansen, E. H. (2014). Dynamic Earth. New York, NY: Jones & Bartlett publishers.

Number 3

Faults, Hypocenters, and Epicenters

Faults, hypocenters, and epicenters are closely related terms that define various aspects of an earthquake. The fault refers to a point on the earth’s crust where a slip occurs leading to a release of energy and hence an earthquake. When faults slip over each other or collide, release of energy occurs leading to an earthquake. The hypocenter is a point on the earth’s crust where the seismic waves initially occur. When a slip occurs or when rocks break along the fault line, release of energy occurs, leading to seismic waves, which causes the ground to shake (Hung et al., 2010). The epicenter refers to a point located on the ground surface and directly above the hypocenter.

The statement that faults experiencing no active creep may be considered safe is wrong. Creep movements reduce the likelihood of an earthquake occurring due to stress on the rocks around the fault line. Faults that are experiencing no active creep may indicate two things. First, the sheer stress generated by rocks may be relatively small to cause the rocks to break along the fault line. In such a scenario, the fault may be considered inactive. On the other hand, the rocks could be locked in a way that hinders creep. As such, elastic strain slowly accumulates on the rocks along the fault lines. In future, the rocks may be unable to bear the strain and undergo breakup. This can lead to an earthquake even though there was no creep.

Reference

Hung, C. J., National Highway Institute (U.S.), & Parsons, Brinckerhoff, Quade & Douglas. (2010). Technical manual for design and construction of road tunnels–civil elements. Washington, D.C.: U.S. Dept. of Transportation, Federal Highway Administration, National Highway Institute.

Explain why Africa and South America are moving apart

Contrary to what many think, the earth’s crust is not made up of a single continuous plate, but rather several plates that float on the molten rocks of mantle. Due to high temperatures within the earth’s core, the mantle exists in molten state (Codrington, 2005). Closer to the earth’s surface, the mantle becomes increasingly solid. The molten rocks of the mantle move slowly due to convectional currents. This slow movement causes the plates to drift either apart or close to one another. The plates that make Africa and South America are slowly drifting apart due to currents within the mantle. A part of South American’s coast line bears a similar shape to that of West Africa’s coast line, indicating that the two continents may have been joined together but slowly drifted away due to currents within the mantle (Codrington, 2005). These molten rocks under both continents are moving in opposite directions, thus causing drifting apart.

Reference

Codrington, S. (2005). Planet geography. Sydney: Solid Star Press.

Western Civilization-Sparta and Athens

Earth Science

Question

Have you, or someone you know, personally experienced an earthquake? Describe the moment just before the earthquake. What was the earthquake itself like? How was your life and the local population affected?

Or:

Imagine that your city was hit by a major earthquake. What kind of damage would you see? For example, are there dams upstream of your city that might burst and release floodwaters? Are there any major pipelines that would be vulnerable, leading to fires? Are you near a coast? Is there a threat of tsunamis? Do you think your city’s building codes are enough to withstand a major earthquake?

unit 4

Discuss the geologic history of the area where you live or grew up. Discuss some of the major factors that might have played a role in shaping the local terrain (major rivers, sea-level changes, volcanoes, ancient sea beds, glaciers, earthquakes, etc.). If needed, spend a few minutes researching your state on-line, (search for your state and “geologic history”). Be sure to list all sources that you use in your answer.

Based on the descriptions of the other students, respond to a student who lives in a place that you would like to live or visit. What is it about the geology of the place that intrigues you? Be sure to keep the discussion based in science

unit 5

This NASA video shows one example of how humans have impacted the oceans. Discuss at least two other examples of how human activities impact oceans. You might consider fisheries, oil exploration, transportation, dams, global climate change, shoreline development, etc. Be sure to explain how these activities affect the oceans.In your response to another student, discuss ways that we might lessen our impact on the oceans.

unit 7

When comparing tornadoes and hurricanes, which do you consider more destructive and why? You might compare how they differ in size, speed, predictability, or damage. Have you ever experienced either? Describe your experience.

unit 8

Part I: It has been stated that we know more about the surface of the moon than we do the oceans. Compare what you have learned in Unit V with this Unit. Do you think, as a nation, we should invest more resources in space exploration or in ocean exploration? Why? Support your answer.

Part II: Briefly describe one thing (from discussion boards, assessments, or readings) you learned in this class that will probably stick with you for a long time. Was there a topic that you struggled with?

Sample paper

Earth Science

Unit 3

My friend described to me the experience of an earthquake. While watching a football match in a hotel, there was some rumbling noise. Suddenly, the tables and chairs started shaking. After about a minute, the shaking intensified to the point that loose objects were falling on the floor. After about three minutes, the shaking subsided and they all run out to a flat ground outside the hotel. Some buildings collapsed while others developed cracks along the walls. For the rest of the week, business came to a standstill, as the entire community was involved in searching for people buried under the rumble.

Unit 4

One of the major factors that has shaped the area I live is the action of rivers and ocean levels millions of years age. Tennessee region comprises of three major physical landforms, which include highlands and basins, mountains, and the river valley plain. The area is divided into three major divisions namely East Division, Middle, and West Tennessee Division (Rodgers, 1993). During the Paleozoic era, deposition of sediments to the Mississippian occurred, affecting the Middle Tennessee region. These sediments came from the Ordovician period. The sediments comprised of deep ocean limestone. During the Mesozoic era, sediment deposition occurred along the Tennessee River basin. During the Cenozoic era, there was a significant drop in the seal level (Rodgers, 1993). This led to formation of the deep Tennessee River valley. One of the place I would like to visit is the Utah region to learn more about the canyons and the rocky terrain.

Unit 5

Human activities such as oil exploration significantly impact the marine environment. Oil exploration in the sea has resulted in oil spills over the past, which negatively affect the marine environment. In addition, dangerous substances such as lead, mercury, arsenic, and others contaminate ocean waters during oil mining (In Allen, In Pondella, & In Horn, 2006). All these lead to destruction of marine life. Global climate change has led to melting of the polar ice caps. This has contributed to rising sea levels. The oceans are absorbing more heat than usual due to climate change. This has led to high sea surface temperatures, which in turn affects currents and water salinity. Humans can lessen the impact of dam construction on the oceans by building smaller dams. Large dams have a high impact on the river flow, which affects the marine environment.

Unit 7

Hurricanes are more destructive. There are two reasons why they are destructive than tornadoes. First, hurricanes last longer than tornadoes. Hurricanes can last for more than two days and cover a wide region, while tornadoes are localized and cover a small region. Secondly, hurricanes are sometimes accompanied by heavy rainfall and flooding, which adds to their destructive power. I have experienced a hurricane in the past. The hurricane had strong powerful winds accompanied by heavy downpour.

Unit 8

The nation should invest more in ocean exploration. Vast parts of the ocean remains unexplored even today. Exploring the ocean may not be an enormous challenge since the technology is already in place to facilitate deep-sea exploration. This can help in documenting additional sea species and learning more about the evolutionary history. While space exploration is interesting, the current technology is limited due to the vast distances. As such, space exploration is unlikely to yield any tangible results in the near future. One of the things I learnt from the course and will stick me for a long time is about the water, carbon, and nitrogen cycles. The topics were relatively easy, thus I did not struggle with any topic.

 

Reference

In Allen, L. G., In Pondella, D. J., & In Horn, M. H. (2006). Ecology of marine fishes: California            and adjacent waters. Berkeley: University of California Press.

Rodgers, J. (1993). Geological map of East Tennessee with explanatory text. State of Tennessee   Department of Environment and Conservation Division of Geology. Retrieved from             http://www.tennessee.gov/assets/entities/environment/attachments/geology_bulletin-         58_2text.pdf

Hurricanes Web Assignment

Earth Science

Question

Using a search engine such as Google, research a mineral or minerals that are mined in your area. Then read about the process(es) used to mine this mineral. What are some of the safety or environmental concerns associated with this type of mining? In your comments to another student, discuss whether you think the economic benefits outweigh the safety or environmental concerns. (calcite is minded in my area) NO WORD MINIMUM

List and describe the different characteristics of sedimentary rocks and discuss the processes that change sediment into sedimentary rock.

How is a scientific hypothesis different from a scientific theory? How does a scientific theory differ from a regular theory (i.e., a non-scientific theory in the way the term is used by lay people)?

Explain, with examples, how a change in each sphere will affect each of the other three spheres.

Sample paper

Earth Science

Mining Calcite

Calcite is one of the most abundant minerals that occur in the earth’s crust. Calcite occurs in the sedimentary rocks. It may occur either deep within the earth’s crust or on the surface of the earth (Azcue, 1999). As such, calcite extraction occurs through underground mining or surface mining. One of the environmental concerns associated with underground calcite mining is the disruption of underground water systems such as aquifers and flow of streams. Since calcite occurs in limestone region, underground mining may lead to development of sinkholes on the land. Man-made sink holes are dominant in areas having underground mining (Azcue, 1999). On the other hand, surface mining leads to destruction of the natural vegetation, leading to development of derelict land. The economic benefit of mining calcite outweighs safety or environmental concerns especially where environmental restoration occur following mining.

Characteristics of sedimentary rocks

Sedimentary rocks form through lithification of rock particles, which undergo transportation and are deposited in layers to form compact sedimentary rocks. The first characteristic of sedimentary rocks is stratification, which involves having multiple layers (Stewart, 2002). The second characteristic is fossilization. Sedimentary rocks contain animal and plant fossils that date back different historical periods. Another characteristic is porosity, which means that water can percolate through them. Sedimentary rocks weather easily. Lastly, sedimentary rocks formed near coastlines contain marks and imprints caused by waves. The process of lithification occurs when weathered rock debris are transported from one place to another. The rock particles become sorted and rounded during the transportation process (Stewart, 2002). Upon deposition, the weathered rock debris hardens due to pressure from overlying material. Dead organic matter also undergoes lithification, forming part of sedimentary rocks.

Hypothesis

A scientific hypothesis is a statement that explains an observable phenomenon, or a prediction of the probable causal relations among different phenomenon. On the other hand, a scientific theory is an explanation of observable phenomenon that is verified or backed up by well-substantiated evidence. A scientific theory is based on evidence, while a regular theory links fact without concrete evidence.

Effect of change in each sphere

A change in hydrosphere can affect the amount of water vapor in the atmosphere, causing changes in precipitation. A change in the hydrosphere can affect the biosphere by changing precipitation rates. High precipitation rates may lead to flooding and landslides, while low precipitation rates can lead to events such as drought (Ernst, 2000). This may lead to destruction of natural ecosystems. Changes in hydrosphere can affect geosphere by changing the rate of weathering and erosion.

A change in atmosphere can affect the level of water held up in the hydrosphere (Ernst, 2000). For instance, climate change may lead to excess water being held in oceans due to melting of ice in the polar region. Changes in atmosphere can affect the biosphere. For instance, high number of dust or smoke particles in the air may impact the ability of animals to breathe, causing deaths of species. Ash particles in the atmosphere from volcanoes may affect the geosphere. For instance, the ash particles may be deposited in far off areas causing a change in PH of the soil.

Changes in the biosphere such as reduced vegetation can affect the geosphere (Ernst, 2000). For instance, reduced vegetation may lead to increased erosion and weathering of rocks. Changes in biosphere such as reduced vegetation cover may affect the amount of water vapor in the atmosphere and consequently precipitation rates. Reduced vegetation cover may affect precipitation in an area. This may affect the hydrosphere by decreasing the amount of water in streams.

Changes in geosphere such as increased erosion rates may affect the hydrosphere by increasing the amount of sediments in stream water, lakes and oceans (Ernst, 2000). Changes in geosphere such as changes in PH levels of the soil may affect the biosphere by causing changes in the growth of plants. Dry conditions in geosphere may lead to high rates of wind erosion and increase in dust particles in the atmosphere. This may alter the quality of air.

References

Azcue, J. M. (1999). Environmental Impacts of Mining Activities: Emphasis on Mitigation and    Remedial Measures. Berlin, Heidelberg: Springer Berlin Heidelberg.

Ernst, W. G. (2000). Earth systems: Processes and issues. Cambridge: Cambridge University       Press.

Stewart, M. (2002). Sedimentary rocks. Chicago, Ill: Heinemann Library.

Hurricanes Web Assignment

GEOLOGY

Question

Describe the characteristics a substance must possess in order to qualify as a mineral.

question 11

List the eight most abundant elements in the continental crust.

question 12

How is a scientific hypothesis different from a scientific theory? How does a scientific theory differ from a regular theory (i.e., a non-scientific theory in the way the term is used by lay people)?

question 13

Explain, with examples, how a change in each sphere will affect each of the other three spheres.

Sample paper

GEOLOGY

Question 10

A mineral is any class of substance occurring in nature and usually comprises of inorganic substances of the definite chemical composition. Some of the characteristics of minerals include:

  1. Solid – a mineral should retain its shape and density when not confined.
  2. Inorganic – all minerals should not contain materials that come from animals and plants.
  3. Naturally occurring – in most cases, minerals should occur and be delivered in their natural form that is not human influenced.

Question 11

  1. Oxygen
  2. Silicon
  3. Iron
  4. Aluminum
  5. Sodium
  6. Magnesium
  7. Calcium
  8. Potassium

Question 12

Science is an important part of human life and in recent years, people have come to like and love science after a series of discoveries. Scientific knowledge is a body of techniques that helps in investigation phenomena thus acquiring new knowledge and insight about the same. Moreover, scientific knowledge and discoveries help to correct and integrating past knowledge (Miall, 2013). However, the body uses specific terms that are different from each other. Such terms include scientific hypothesis, scientific theories, and regular theory.

Scientific hypothesis differs from scientific theories in that scientific hypothesis is an educated guess that in based on previous and past knowledge and observations that may change with time. In most cases, a scientific hypothesis is regarded as the building block for any observations and discoveries. On the other hand, scientific theories are well-defined explanations and descriptions of some aspect of the natural and real world and phenomena that result from repeated experiments.

In addition, there is a difference between scientific theory and a regular theory. A scientific theory consists of a set of rules that explains observed phenomena based on empirical facts and studies while a regular theory is an evolved version of a hypothesis linking facts but it is based on speculations and cannot take to be the truth as it implies doubts.

Question 13

The earth is made up of four spheres which are connected to each other to make it look like a single structure. The four spheres in the earth’s structure include Geosphere, hydrosphere, lithosphere and biosphere. Changes in one sphere affect all other spheres and in most cases, these changes are brought by human activities that cause imbalance in the atmosphere.

The lithosphere acts as the home for all cold, hard solid and the semi-solid earth below the earth’s crust, and geosphere describes all the rocks, minerals and the ground that are found in the earth. Moreover, the hydrosphere is made up of all mass water bodies while the biosphere comprises of all living organisms on the planet (Millot, 2013).

When a plant (biosphere) absorbs more can IV oxide for photosynthesis purpose, there in an increase in heat in other spheres which in turn causes imbalance resulting in adverse effects such as global warming. When the heat increases, there is an increase in the proportion of the incident radiations reflected by the earth’s surface causing the ice (hydrosphere) to melt and increase in the space occupied by deserts (geosphere) which in turn increases the amount of dust particles (lithosphere) in the earth’s atmosphere. Moreover, when the rain falls (hydrosphere), it causes soil erosion (geosphere) which sweeps away plants and small living organizes in the soil (biosphere) and leaves big trenches that are dug by the running water (lithosphere).From the above examples, it is clear that change is one sphere leads to changes in all other spheres which may cause negative effects on the earth atmosphere.

References

Miall, A. (2013). The geology of fluvial deposits: sedimentary facies, basin analysis                      , and petroleum geology. Springer.

Millot, G. (2013). Geology of Clays: Weathering· Sedimentology· Geochemistry.               Springer Science & Business Media.

Parallax angle and Hertzsprung-Russell diagrams

Parallax angle and Hertzsprung-Russell diagrams

Part 1: Finding the Distance to Stars Using the Parallax Angle

Instructions:

 

Read Chapter 15 and Appendix D (pp. 543-545) in the textbook and the background information below.

Answer the three questions at the bottom directly in this lab worksheet.

 

This NASA web page provides additional explanation:

 

http://imagine.gsfc.nasa.gov/features/cosmic/nearest_star_info.html

 

Background:

 

Stellar Parallax is the apparent shift in the location of a star due to the orbit of the Earth.  In other words, the star will appear to be in a different place depending on the line of sight from the Earth. By knowing the diameter of Earth’s orbit and by measuring the angle of apparent shift (the parallax angle), astronomers can calculate the distance to the nearby stars using trigonometry. This method has been used for centuries. The ancient Greeks were able to measure some of the closest stars this way. Today, sophisticated telescopes have greatly enhanced this method. Figure 1 is a graphic from your textbook showing how this works:

 

Assignment:

 

For this assignment, you will determine the distance to a star, “HT Cas”, using the method of stellar parallax. Figure 2 and 3 below are photos of HT Case, taken six months apart:

Fig 2. Image of HT Cas taken 06/96 Fig. 3. Image of HT Cas taken 12/96

 

When we super-impose these photos, we get the following image (figure 4):

You can see that the position of the star appears to have changed over the six-month time period.  However, it is actually the angle from which the photos were taken that has changed.  During that 6-month period, the Earth moved from one side of the sun to the other.

 

Using a stellar astrometric catalog, we find that the two stars closest to HT Cas are a distance of 0.01 arcseconds apart. Based on this information, we can estimate that the angle of shift of HT Cas (the parallax angle) to be approximately 0.015 arcseconds apart.

 

We also know that the radius of the Earth’s orbit is 1.0 A.U. (astronomical units).

Using these two measurements, we can then determine the approximate distance to HT Cas using the following equation:

 

d= distance to HT Cas

a=radius of the Earth’s orbit

p=parallax angle

 

  1. (10 points) Given the above equation and information provided, about how far away is HT Cas?
  2. 133 parsecs
  3. 67 parsecs
  4. 33 parsecs
  • 015 parsecs
  1. (10 points) Your answer was calculated in parsecs. Given that 1 parsec = 3.2616 light years, about what is the distance to HT Cas in light years? (Your answer in parsecs X 3.2616 light years = The Distance to HT Cas in light years).
  2. 025 light years
  3. 217 light years
  4. 434 light years
  5. 219 light years
  1. (30 points) Based on your answer, do you think this is a star that we might be able to send a space probe to? Why or why not?  Support your answer.
Judging by the distance and current technological advancements, it might not be possible to send a space probe. The current space probes move through space at the speed of about 20 km/s. This is a tiny fraction of the speed of light, which moves through space at a speed of 300,000 km/s. Thus if humans were able to accelerate a space probe to the speed of light, it would still take a long time to reach the star. As such, it might not be possible to send a space probe due to the distance involved.

 

Part 2: Using a Hertzsprung-Russell Diagram

 

Instructions: After reading the Unit VIII lesson, click here to access the NASA web page “Stars” and answer the questions below using Figure 5. You can also copy and paste the web address into your browser:

 

http://science.nasa.gov/astrophysics/focus-areas/how-do-stars-form-and-evolve/

Background:

 

Notice that the stars in Figure 5 are not uniformly distributed. Rather, about 90 percent of all stars fall along a band that runs from the upper-left corner to the lower-right corner of the H-R diagram. These “ordinary” stars are called main-sequence stars. As you can see in Figure 5, the hottest main-sequence stars are intrinsically the brightest, and, conversely, the coolest are the dimmest. The absolute magnitude of main-sequence stars is also related to their mass. The hottest (blue) stars are about 50 times more massive than the Sun, whereas the coolest (red) stars are only 1/ 10 as massive. Therefore, on the H-R diagram, the main-sequence stars appear in decreasing order, from hotter, more massive blue stars to cooler, less massive red stars (Lutgens, Tarbuck, & Tasa, 2014).

 

Assignment: Use Figure 5 to answer the questions. Once all questions have been answered for both part 1 and part 2, save this worksheet with your last name and student number and upload to Blackboard for grading.

 

  1. (10 points) Main Sequence stars can be classified according to which characteristics? What are the characteristics of our Sun?
Main Sequence Star Classification

Classification based on the nature of their death.

The time they take to mature.

They can be classified according to luminosity.

They can be classified according to color.

Relative size compared to the sun.

Characteristics of the sun

The sun takes approximately 50 million years to mature.

The maturity phase may take approximately 10 billion years.

The sun derives its energy from a nuclear fusion reaction involving hydrogen gas, which is converted to become helium. Hydrogen makes up 70% of the mass, Helium taking up 28%, and some iron taking the rest.

The sun has a diameter of about 1,390,000 km.

The average temperature of the sun is 6,000K.

 

 

  1. (10 points) Which main sequence stars can be found with a surface temperature of between 3000K-4000K? Which stars have a luminosity about 100 times less than that of the Sun?
Main sequence stars with a surface temperature of between 3000K-4000K.

Aldebaran star

Red dwarfs

Arturus

Stars with luminosity less than 100 times the sun

White Dwarf

Novae

Supernovae

Spica

Rigel

 

  1. (30 points) Briefly describe the solar evolution time-line of a common star like our own from formation through collapse.
Stars emerge from clouds of dust present in most galaxies. Deep within the clouds of dust, turbulence occurs leading to formation of knots or cosmic textures. The knots are areas that have differences in texture and other properties arising from varying cooling rates. These knots bear a sufficient mass, which means that the cloud of dust is pulled towards the center by the resulting gravitational force. At the center of the cloud, temperatures begin to rise as materials collapse. The process continues and a young star called a protostar emerges.

Related:

Hurricanes Web Assignment

Hurricanes Web Assignment

Question

Hurricanes Web Assignment

Access the National Oceanic and Atmospheric Administration (NOAA) Create-A-Cane site here, or copy and paste this address into your browser http://www.nhc.noaa.gov/outreach/games/canelab.htm. Follow the instructions below to answer the questions.

Use this interactive game to create a “perfect storm.” Go through and adjust the atmospheric conditions to produce a powerful hurricane. If you get the conditions perfect, you will get a score of 80 and the simulation will prompt you to answer a few questions. If you go on to answer the questions correctly, you can boost your score to 100. It may take you several attempts to get your perfect storm and you do not need to report your score. Use the help buttons to understand how each factor contributes to the formation of the storm. Once you are satisfied with your score, answer the questions below. Copy and paste the questions into a word document. Once you have answered all the questions, save the document using your last name and student ID as the file name and upload to Blackboard for grading.

  1. What types of winds were required in each level of the atmosphere? Describe the wind speed and direction at each level.
  2. Why is it critical that all levels blow in the same direction to form a tropical storm? What happens when you have lower winds blowing a different direction than upper winds?
  3. It seems intuitive that stronger winds would be better for forming a hurricane. Why is this not the case?
  4. What was the ideal latitude range for the formation of the tropical storm? Why?

ES 1010, Earth Science 4

  1. Given that tropical storms/hurricanes require high moisture and temperatures, why can’t tropical storms form at the equator (0 degrees latitude), where temperatures and moisture are generally very high?

  2. What moisture level was required for each of the atmospheric layers?

  3. Why is moisture critical to form a hurricane?

  4. How did the sea temperature affect your score? Why?

  5. Which of the above factors seem to make the biggest difference in your score and why?

  6. Explain why hurricanes dissipate so quickly once they make landfall

Sample paper

Hurricanes Web Assignment

Question 1

Each level of the atmosphere requires winds with a low shear. This includes the upper-level, mid-level, and low-level winds. In addition, the winds should blow from the same direction.

Question 2

In order for a hurricane to form, wind must blow from the same direction at all levels. It is important that winds blow in the same direction to sustain the heat of the hurricane. When winds move in the same direction, the strength of the hurricane is maintained since there is no shearing. On the other hand, if the winds move in different direction, the storm dissipates due to the disturbances in the vertical flow of the cold and warm air.

Question 3

Weak winds are suitable for forming a hurricane. This is because they give room for the formation of a tropical wave, which in turn gives rise to convections. Where there are strong winds, convection cannot occur, which means that warm humid air cannot be able to rise to replace the cold unstable air.

Question 4

The ideal latitude for the formation of a tropical storm is 5 degrees to 30 degrees north. In this region, the effects of Coriolis Effect are strong enough to create a spinning motion for tropical storms. The Coriolis Effect maintains a temperature gradient between the upper levels and lower levels of the atmosphere during storm formation. In the equatorial regions, the Coriolis Effect is zero.

Question 5

Tropical storms cannot form at the equator due to lack of Coriolis Effect, which produces the shearing motion. Another reason relates to the behavior of winds, which flow into low-pressure regions and often causes a vertical wind shear that disrupts the formation of convections.

Question 6

A high level of moisture level was required in each of the atmospheric levels.

Question 7

Moisture is critical in the formation of a hurricane because it helps in the development of a thunderstorm. Thunderstorm development is significant because it helps in latent heat release mechanism, which is one of the key drivers or sources of energy of a tropical cyclone.

Question 8

The minimum sea temperature required for the formation of a tropical cyclone is 26.5 C. When the sea temperature is low, the score is also low. This is because a tropical storm requires the sea temperatures to be warm, while the upper atmospheric temperatures are cold, which creates a pressure different. Additionally, warm temperatures contribute to high moisture levels.

Question 9

The factor that makes the biggest difference is sea temperatures. This is because higher sea temperatures provide the energy needed for storm development.

Question 10

Hurricanes dissipate quickly once they reach landfall because there is lack of warm ocean surface, which provides the required moisture for sustaining the hurricane. The ocean acts as the source of energy for a hurricane by extracting heat from the ocean.

Related:

Parallax angle and Hertzsprung-Russell diagrams