Showing posts with label layers of atmosphere. Show all posts
Showing posts with label layers of atmosphere. Show all posts

Sunday, April 8, 2012

Meteorology 211 - Assignment 4


    Meteorology 211
    Spring Quarter 2011
    Homework Assignment #4

    Due Date: Friday, May 27

    Answer the following questions based on the assigned reading and classroom discussions.  Answers must be typed. Please use complete sentences.

    [For the first two questions, please go back and re-read pages 28-31 in chapter 2 (about ozone).]

    1)  What are halocarbons, and what effect can they have on ozone concentrations in the stratosphere?
        
    Halocarbons are certain chlorine-, fluorine-, and bromine- containing compounds, which destroy the ozone. The best known compound chlorofluorocarbons (CFCs). In the stratosphere UV radiation breaks down CFCs releasing free chlorine atoms. Chlorine then reacts with ozone to form chlorine monoxide (ClO) and ordinary (molecular) oxygen, when chlorine monoxide meets a single oxygen atom, free chlorine forms again.



    2)  How would you respond to a person who says: “We have to fix the hole in the ozone layer because it’s letting too much extra heat from the Sun through and is causing global warming.”
       
    The ozone is not really a layer, rather similar to clouds that drift. Therefore an “ozone hole” is actually a region of low ozone concentration.



    3)  Examine the lower panel (labeled b) on Figure 9.1 on page 176 of the textbook. Notice that the black curve and the blue curve are not in close agreement after about the middle of the 20th century. What does that difference signify?

    The difference in the black and blue curve after the 20th century is because anthropogenic forcing was not taken into account and it was roughly the time period in which the industrial revolution and use of fossil fuel was increasing. The models required the input of anthropogenic forcing, specifically those due to greenhouse gases and aerosols.



    4)  In class, and in the course module, I refer to “business as usual”. In the context of climate change issues, what does that mean? In your own personal opinion (no right or wrong answers here), do you think human society will continue to do “business as usual”? If so, for how long?

     
    The expression “business as usual” refers to society continuing to do the same things they are doing (extreme use of fossil fuels, release of greenhouse gases, etc…) without concern for what is happening (global warming). I think society will continue business as usual as long as they are not being affected directly by it. (out of sight out of mind basically)


    5)  What are “emission scenarios”, and why is it necessary to do multiple climate model runs using different scenarios?

    “Scenarios are [alternative] images of the future…They are neither predictions nor forecasts. Rather, each scenario is on alternative image of how the future might unfold.” (Mathez 2009, PG 178). It is necessary to do multiple climate model runs using different scenarios because of the widely varying future world.



    6)  In general, how are worldwide precipitation patterns expected to change during the rest of this century, based on climate model predictions?


    Precipitation patterns are projected to change, with large increase in rainfall in equatorial regions, less precipitation in the mid-latitudes, and somewhat greater precipitation at high latitudes. The changes in precipitation patterns are reflected in the changes in air pressure.

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.

Meterology 211 Assignment 1

Meteorology 211  
Spring Quarter 2011
Homework Assignment #1
***Due Date: Friday, April 15***
Answer the following questions based on the assigned reading and classroom discussions.  Answers must be typed. Please use complete sentences.
1)  a. How many layers are there in the Earth’s atmosphere?
Vertical structure(layering --->Figure 2.1 in Book):
There four layers of the Atmosphere which include the thermosphere, mesosphere, stratosphere, and the troposphere.
-Thermosphere
-Mesosphere
-Stratosphere ---"The Ozone Layer"
-Troposphere ---All of the weather originates in this layer.
     b. In which of these layers does virtually all of our observable weather occur?
         (precipitation, storms, etc.)
All most all of our observable weather occurs in the troposphere.
2) a. In which atmospheric layer do we find most of the naturally-occurring ozone
        in the atmosphere?
Most of the naturally-occurring ozone is located in the stratosphere.
    b. Explain how it is that ozone can be considered a good thing in one layer of
        the atmosphere and a bad thing in another layer.
Ozone which is contained in the stratosphere, absorbs harmful ultraviolet radiation from reaching the Earth's surface. However in the troposphere Nitrogen oxide in the presence of sunlight produces ozone (photochemical smog). Ozone (photochemical smog) is a bad thing in the troposphere, It can cause health issues, it is an air pollutant, and  toxin.
3) a. How many prevailing surface wind zones do we find on Earth?
There are four Types of Prevailing Winds  which include trade winds, westerlies, polar easterlies and jet streams.
(1)Trade Winds : In olden days, sailors heavily depended on these prevailing winds to sail from Europe to America. The northeast trade winds are found between the latitudes of 30 to 0°N and the southeast trade winds occur between 0 to 30°S latitudes.
(2)Westerlies : These prevailing winds are found below the Ferrel circulation cell in the mid latitudes.
(3)Polar Easterlies are prevailing winds that are permanent cold winds which form a part of the polar circulation cell. These winds can mix with the Gulf Stream to form very violent and strong tornadoes and thunderstorms.
(4)Jet Streams are prevailing winds which are very swift currents of the higher level.
    b. What do we call the wind zones on either side of the equator (between
        the equator and about 30˚N and S latitudes)?
The wind zone on either side of the equator is called the Trade Winds.
    c. What do we call the wind zone that includes the majority of the continental
        United States?
The wind zone that includes the majority of the continental United States is the Westerlies wind zone.
4) Explain what is meant by the “high thermal (or heat) capacity” of water, and what effect this property of water has on the average climate of continental coastal regions.
Water absorbs or releases more heat than many substances for each degree of temperature increase or decrease. In other words water has an unusual ability to hold heat, it maintains a relatively stable temperature which in turn moderates the temperatures of coastal regions.
For example, local fog or mist is likely to occur if a lake cools the surrounding air enough to cause saturation; consequently, small water droplets are suspended in the air. Large bodies of water, such as the oceans or the Great Lakes, have a profound influence on climate. They are the world's great heat reservoirs and heat exchangers and the source of much of the moisture that falls as rain and snow over adjacent land masses. When water is colder than the air, precipitation is curbed, winds are reduced, and fog banks are formed.
5) Why is the ocean salty, and why does it not keep getting saltier over time?
The rain that falls on the land contains some dissolved carbon dioxide from the surrounding air. This causes the rainwater to be slightly acidic due to carbonic acid. The rain physically erodes the rock and the acids chemically break down the rocks and carries salts and minerals along in a dissolved state as ions. The ions in the runoff are carried to the streams and rivers and then to the ocean. Many of the dissolved ions are used by organisms in the ocean and are removed from the water. Others are not used up and are left for long periods of time where their concentrations increase over time.Rivers and surface runoff are not the only source of dissolved salts. Hydrothermal vents are recently-discovered features on the crest of oceanic ridges that contribute dissolved minerals to the oceans. These vents are the exit point on the ocean floor from which sea water that has seeped into the rocks of the oceanic crust has become hotter, has dissolved some of the minerals from the crust, and then flows back into the ocean. With the hot water comes large amounts of dissolved minerals. Estimates of the amount of hydrothermal fluids now flowing from these vents indicate that the entire volume of the oceans could seep through the oceanic crust in about 10 million years. Thus, this process has a very important effect on salinity. The reactions between seawater and oceanic basalt, the rock of ocean crust, are not one-way, however; some of the dissolved salts react with the rock and are removed from seawater.
A final process that provides salts to the oceans is submarine volcanism, the eruption of volcanoes under water. This is similar to the previous process in that seawater is reacting with hot rock and dissolving some of the mineral constituents. Several processes can cause salinity to change. These processes include Evaporation and Precipitation with increase and decrease saltiness, freezing and thawing add and removes fresh water affecting saltiness. The global ocean conveyor system also regulates the saltiness of the ocean.
6) a. How many distinct vertical layers do we usually find in the ocean?
The ocean has three major layers. The mixed layer, which extends 20 to 200 meters in depth, and is where most of the oceans heat is stored. The thermocline, in this layer temperature decreases and salinity increases. The thermocline extends 500 to 900 meters. Below the thermocline is the deep zone/layer, in this layer salinity and temperature vary only slightly with depth.
    b. What physical properties of water cause the ocean to form layers?
The physical properties of water which cause the ocean to form layers are density, temperature, and salinity.
These physical properties cause less dense stuff to float on denser stuff. As well as causing Warm water to float on cold water, and less salty (fresher) water to float on saltier water.
7) What is a “subtropical gyre”, and how many of those do we find in the Earth’s oceans?
The five most notable gyres include North Atlantic Gyre, South Atlantic Gyre, Indian Ocean Gyre, North Pacific Gyre, South Pacific Gyre, Subtropical gyres.
The currents of the ocean are mainly affect by wind. Like wind the currents of the Ocean are affected by the Coriolis Effect, causing them to form distinct patterns, overpowered by subtropical gryes, or semicircular current systems on either side of the equator. The generally easterly trade winds push the westward flowing arms of the subtropical ocean gryes near the equator. The flow as a result generates eastward-flowing equatorial countercurrents both at and below the surface.
8) Look at Figure 3.8 on page 46 of the textbook, which depicts the “global ocean conveyor system”. Obviously this moves (or “conveys”) a lot of water around the Earth’s oceans, but what other important property does it also carry throughout the oceans?   
The meridional overturning circulation, represents an enormous transport of heat from north to south. This illustrates how the ocean can have a significant moderating effect on regional climate.
9) El Niño and La Niña are names for two different (opposite) atmospheric/oceanic circulation patterns that sometimes develop in the equatorial Pacific Ocean. Not many people live in the equatorial Pacific – so why should those of us in the rest of the world care about these events?   
El nino and la nina affect the climate and ocean condition in a slightly widespread manner. These abnormal circulation patterns can cause disruption in fish populations and migration patterns. These circulation patterns can change the temperature of the ocean waters near the coast which can affect the climate bringing colder/wetter or warmer/drier weather to North and South America.