Showing posts with label alternative power. Show all posts
Showing posts with label alternative power. Show all posts

Sunday, April 8, 2012

Meteorology 211 - Assignment 5

Meteorology 211
Spring Quarter 2011
Homework Assignment #5
Due Date: Friday, June 10
Answer the following questions based on the assigned reading and classroom discussions.  Answers must be typed. Please use complete sentences.
1)  As of 2005, what percent of the global total energy production was accounted for by fossil fuels? What percent of the total did renewable energy contribute?
    
In 2005, more than 3/4 of total global energy production was through the use of fossil fuels. Petroleum led with over 43.4 percent of the global total, followed by natural gas (15.6 percent) and coal (8.3 percent). North America is the largest consumer of fossil fuels, utilizing nearly 25 percent of global resources.
2)  Why is coal considered to be the “dirtiest” fossil fuel?
   
Coal is considered to be the "dirtiest" fossil fuel because of the great amount of greenhouse gases they emit. Even the so call "clean coal" where they say that washing coal reduces the sulfur and other pollution causing minerals during combustion, however the washing process yields large quantities of waste containing high concentrations of dangerous pollutants that must be disposed of somewhere. Large waste piles are often left exposed to the elements where rain washes through the waste piles, picks up heavy metals and other pollutants, and becomes a toxic runoff that eventually contaminates ground water and streams. After burning, coal ash is often stored in loosely regulated ponds where toxins such as arsenic, lead, mercury, and heavy metals create yet another toxic soup


3)  a. What is carbon sequestration?
     b. What are some of the uncertainties and potential problems with carbon
         sequestration?
(a)Carbon sequestration is the capture of carbon dioxide (CO2) and may refer specifically to:
-The process of removing carbon from the atmosphere and depositing it in a reservoir. (When carried out deliberately, this may also be referred to as carbon dioxide removal, which is a form of geo-engineering.)
-The process of carbon capture and storage, where carbon dioxide is removed from flue gases, such as on power stations, before being stored in underground reservoirs.
-Natural biogeochemical cycling of carbon between the atmosphere and reservoirs, such as by chemical weathering of rocks.
(b)Some uncertainties and potential problems of carbon sequestration are:
-Carbon dioxide that is stored deep underground where hydrostatic pressure acts to keep it in a liquid state, however reservoir design faults, rock fissures and tectonic processes may act to release the gas stored into the ocean or atmosphere.
-Financial cost of the use of the technology would add an additional 1-5 cents of cost per kilowatt hour, according to estimate made by the Intergovernmental Panel on Climate Change. The financial costs of modern coal technology would nearly double if use of CCS technology were to be implemented.


4)  a. What are the four issues that must be overcome in order for nuclear
         power to expand into a major power source to replace fossil fuels?
     b. Which of these issues concerns you the most? (your opinion)
(a) The four issues that must be overcome in order for nuclear power to expand to a major source of power are:
-Costs: nuclear power has higher overall lifetime costs compared to natural gas with combined cycle turbine technology (CCGT) and coal, at least in the absence of a carbon tax or an equivalent “cap and trade” mechanism for reducing carbon emissions.
-Safety: nuclear power has perceived adverse safety, environmental, and health effects, There is also growing concern about the safe and secure transportation of nuclear materials and the security of nuclear facilities from terrorist attack.
-Proliferation: nuclear power entails potential security risks, notably the possible misuse of commercial or associated nuclear facilities and operations to acquire technology or materials as a precursor to the acquisition of a nuclear weapons capability. Fuel cycles that involve the chemical reprocessing of spent fuel to separate weapons-usable plutonium and uranium enrichment technologies are of special concern, especially as nuclear power
spreads around the world.
-Waste: nuclear power has unresolved challenges in long-term management of radioactive wastes. The United States and other countries have yet to implement final disposition of spent fuel or high level radioactive waste streams created at various stages of the nuclear fuel cycle.



5)  a. What are some of the practical advantages and disadvantages of wind and
         solar power as renewable energy sources?
     b. If you had some extra money to invest in one of these two energy sources,
         which would you invest in, and why?
(a) The practical advantages of  wind and solar power is that it is renewable and over a period of time (the time for you to produce enough energy to pay for the equipment) very cost effective, and eco-friendly in terms of no greenhouse gas emissions.
disadvantages are space and wind turbine requires 1 acre of land, the wind doesn't blow all the time and the sun doesn't shine all the time... however there is a possibility of hooking up to a grid and selling unused energy back to the power company and having it supplied back to you when solar and wind aren't available.
(b) I would choose wind power if I had extra cash laying around because I did an engineering project for designing and implementing a wind turbine...so I could do it more cheaply...as well as there doesn't seem to be a lot of sun in Washington!


6)  What does the author mean on page 215 when he says there is “no silver bullet” when it comes to getting rid of greenhouse gas emissions?
The author means by there is "no silver bullet" that there is no easy fix and not quick fix in correcting and improving the problem in greenhouse gas emissions.  

Meterology 211 - Assignment 3

Meteorology 211
Spring Quarter 2011
Homework Assignment #3
Due Date: Friday, May 13
Answer the following questions based on the assigned reading and classroom discussions.  Answers must be typed. Please use complete sentences.
1)  a. What was the “Paleocene-Eocene Thermal Maximum” and when did it
         occur? 

(a) The Paleocene-Eocene Thermal Maximum was an event that occurred during the Paleocene epoch, 55 million years ago, when an enormous mass of carbon flooded the ocean and atmosphere. (In less than 1000years 1500-4500 gigatons of carbon entered the climate system raising the surface temperature 5 to 9 degrees Celsius and the ocean acidified.


     b. Why is this past event potentially important in understanding what may
         be happening in our current changing climate?
  
(b) The past event is potentially important in understanding what may be happening in our current changing climate because it is analogous of the current situation….1500-4500 gigatons of carbon that entered the climate system in the Paleocene epoch is about the same amount of carbon projected to enter it as a consequence of human activities during the twenty-first century if fossil-fuel use continues to grow at the current pace.


2)  Why is it misleading to refer to the “Ice Age” as a singular past event?
   
The term ice age is somewhat misleading because it does not mean that the planet has been completely and perennially frozen. Rather, during this time the climate has fluctuated rapidly between glacial intervals lasting tens of thousands of years and shorter interglacial intervals. (Mathez, 2009(Pg102))


3)  Describe the three main characteristics of Earth orbital cycles called “Milankovitch Cycles”.
Earth’s orbital parameters of precession (Earth's axis of spin relative to the orbital axis once about every 21,000 years), obliquity(the tilt of the axis of rotation relative to the solar plane….currently 23.5 degrees, changes from 21.5 and 24.5 degrees and back again approximately every 41,000years.), and eccentricity(the degree that Earth's orbit around the sun departs from a circle) as well as the way their individual, cyclical effects combine to influence summer insolation at 65°N latitude. These combined effects of the orbital parameters on insolation are known as Milankovitch cycles.


4) Examine Figure 6.5 on page 110 of the textbook.
     a. From what source(s) of data are the two plots on this figure based?
(a)The two plots are based on analyses of air trapped in Antarctic ice cores compared with the temperature record derived from the composition of ice.
     b. Using just an “eyeball analysis” to compare the two curves, what would
         your conclusion be regarding the relationship between atmospheric
         CO2 concentration and temperature over the last 800,000 years?
(b)My conclusion regarding the relationship between atmospheric CO2 concentration and temperature over the last 800,000 years is that they are very similar.


5) Why can’t carbon-14 dating be used to date the age of rocks?
Carbon-14 dating is dependent upon the presence of Carbon-14 that organisms ingest directly from the atmosphere. Some problems with using carbon-14 dating on rock of whatever kind:
It was never alive,  It never ingested atmospheric carbon-14, It didn't cease to ingest further carbon-14 when it died, seeing as it never died, and Most rock is older than 50,000 years. While rock samples may contain carbon-14, it didn't come directly from the atmosphere.


6)  Look at Figure 7.1 on page 133 in the textbook, and focus in on the period 1940 to about 1975. Describe the trend in global surface air temperature during this period, and explain the prevailing hypothesis on why this occurred.
The intervening interval, from 1940-1979 was characterized by a stable temperature or even slight cooling, possibly due to atmospheric aerosols from human activities. (Mathez, 2009 (Pg132))


7)  Would you be willing to say that Hurricane Katrina in 2005 is direct evidence that global warming is occurring? Why or why not?
   
I don't think that Hurricane Katrina in 2005 is direct evidence that global warming is occurring because hurricanes have always happened….however the magnitude of Katrina may have been influence by climate changes caused by human activities.


8) Over the period 1975-2005, how did the change in average surface air temperature in the Arctic compare to that observed over the Earth as a whole? 
From 1975-2005, Artic surface temperature increased about 0.7 degrees Celsius per decade, which is more than double the 0.3 degrees pre decade rise in global surface temperature.


9)  a. What is the definition of permafrost?
(a) The term permafrost refers to soil or rock that has been below 0°C (32°F) and frozen for at least two years.
      b. Explain how melting Arctic permafrost can act as a positive feedback
          mechanism in global warming.
(b) There is also the important albedo feedback between melting and tempera­ture. Ice is more reflective than water, so as the proportion of open water increases and that of ice decreases, more energy is absorbed by the ocean. Heat thus builds up both in the ocean and in the atmosphere and accelerates the melting.
(Mathez, 2009)


10)  About how much has average sea level risen during the past 21,000 years (the peak of the last glacial maximum)? Was this change entirely due to melting of the large continental ice sheets, or was there another effect on sea level related to climate warming?
About 21,000 years ago, at the most recent glacial maximum, the sea level stood approximately 120 meters (400 feet) below its present level.  With the subsequent melting of the Northern Hemisphere ice cap, sea level rose quickly, but then, according to geological evidence, the rising slowed so that over the past 3,000 years sea level rose about 1 to 2 centimeters (0.4 to 0.8 inch) per century be­fore the twentieth century. Tide gauge data, however, put the twentieth-century rise at a more rapid and accelerating 15 to 20 centimeters (6 to 8 inches), apparently from increased glacial discharge.  

Meteorology 211 - Assignment 2

Meteorology 211
Spring Quarter 2011 
Homework Assignment #2
***Due Date: Friday, April 29***
Answer the following questions based on the assigned reading and classroom discussions.  Answers must be typed. Please use complete sentences.
1)  a. Define what is meant by the Earth’s climate system.
Climate System:
  • Atmosphere (air)
  • Hydrosphere (water)
  • Lithosphere (rock and soil)
  • Cryosphere (sea ice, glaciers, terrestrial ice sheets)
  • Biosphere (living things)
     b. Can you think of another example of a “system” that has interrelated
         components analogous to those of the climate system? (describe it) 
Another example of a "system" that has interrelated components analogous to those of the climate system are similar to those of our body.
2) a. In what form does the energy from the Sun reach the Earth?
The sun emits radiation over a range, or spectrum, of energies, represented in part by the rainbow of colors that make up sunlight. Radiation exists in the form of waves, and radiation wavelength is the inverse of energy: the higher the energy the lower the wavelengths. Therefore, we can think of spectra in terms of energy or wavelength.
    b. What is the definition of the solar constant, and is its numerical value?
The temperature of the Sun's surface - about 6000degrees Celsius(10,800degrees F)- determines both the spectral character and the amount of energy received by the earth. The amount, known as the solar constant, is 1,367 watts per square meter. Averaged over the entire surface of the upper atmosphere, this amount is equivalent to 342 watts per square meter.(A watt is a unit of power equal to 1 joule of energy per second, so radiation intensity is the rate of energy flow per square meter.) Pg.76 Mathez
3)  Define radiative forcing, and explain what the difference is between a positive radiative forcing and a negative radiative forcing.
Radiative forcing is the change, relative to the year 1750, in incoming energy minus outgoing energy in response to a factor that changes energy balance. (the year 1750 is commonly taken as the pre-industrial revolution benchmark for investigating changes in the climate system since then.)
Positive forcing tends to warm the surface while negative forcing tends to cool it.
4) Explain how the atmospheric “greenhouse effect” doesn’t really work like a real greenhouse where we grow plants.
The greenhouse effect IS NOT reflection. The atmosphere absorbs and re-radiates heat it doesn’t trap it like a greenhouse.
5) Explain why it is that volcanic eruptions can produce a natural negative radiative forcing in the atmosphere that can last many months.
Volcanoes influence climate when especially large, explosive eruptions inject sulfur dioxide (SO2) into the stratosphere. Within weeks, the sulfur dioxide reacts with water vapor to form an aerosol composed of particles of sulfuric acid. this stratospheric aerosol circles the globe in two or three weeks. It absorbs solar radiation from above and IR radiation from below , thereby warming the stratosphere but cooling the underlying atmosphere as well as Earth's surface. The aerosol also destroys stratospheric ozone and may influence weather patterns. Because stratospheric aerosol takes two or so years to settle out, the impact on climate lasts well beyond the proximate time of the eruption.
6)  Describe the difference between a positive feedback and a negative feedback in systems in general.
negative feedback like a furnace works when the temperature drops down to a certain temp, at that point the  furnace kick on and begins to heat.
positive feedback like the earth heats up, which causes the surface to get darker and that causes the Earth to heat up more.
7) a. Chapter 4 describes several carbon reservoirs. Which of these stores the
        greatest amount of carbon on Earth?
The "rock" reservoir stores the greatest amount of carbon on Earth, it amounts to some 50 Million gigatons.
    b. Which “surface” reservoir stores the greatest amount of carbon?
The largest by far of the surface reservoirs is the ocean, which holds 39,000 gigatons.
8) What do we mean by anthropogenic carbon emissions, and what are the main activities or processes that produce them? 
Emissions of CO2 and other greenhouse gases as a consequence of human activity-burning fossil fuel, cement production, and other activities, together are commonly referred to as anthropogenic emissions.
9) a. What is causing ocean acidification? [Note: A general answer is okay – you
         don’t need to give me chemical equations, etc.]
Because the atmosphere and the ocean are in chemical equilibrium, as the CO2 content of the atmosphere increases, so does that of the ocean. The CO2 taken up by the ocean goes through a series of reactions that reduce the pH of the water.
     b. Give one example of how ocean acidification could adversely affect ocean
         ecosystems.
Although the pH change may seem small, the acidification is likely to have a profound influence on ocean biogeochemistry, particularly on calcifying organisms. As pH decreases the amount of carbonate is seawater decreases which has the effect of decreasing the stability of calcite and aragonite, the carbonate minerals that constitute the skeletons and shells of calcifying organisms.