Our Dependence upon the Environment

Environmental Issues

36127 Topic: SCI 207 Our Dependence upon the Environment

Number of Pages: 1 (Double Spaced)

Number of sources: 2

Writing Style: APA

Type of document: Essay

Academic Level:Undergraduate

NCategory: Environmental Issues

Language Style: English (U.S.)

Order Instructions: Attached

Week 4 – Assignment 1

Greenhouse Gases and Sea Level Rise Laboratory

[WLO: 3] [CLOs: 1, 3, 5]

This lab enables you to create models of sea level rise resulting from melting of sea ice and glacier ice and examine the effects of this potential consequence of climate change.

The Process:

Take the required photos and complete all parts of the assignment (calculations, data tables, etc.). On the “Lab Worksheet,” answer all of the questions in the “Lab Questions” section. Finally, transfer all of your answers and visual elements from the “Lab Worksheet” into the “Lab Report.” You will submit both the “Lab Report” and the “Lab Worksheet” through Waypoint.

The Assignment:

Make sure to complete all of the following items before submission:

Read the Greenhouse Gases and Sea Level Rise Investigation ManualPreview the document and review The Scientific Method (Links to an external site.)Links to an external site.presentation video.

Complete Activities 1 and 2 using materials in your kit, augmented by additional materials that you will supply. Photograph each activity following these instructions:

When taking lab photos, you need to include in each image a strip of paper with your name and the date clearly written on it.

Activity 2, Step 12 will require you to make a line graph. Should you desire further guidance on how to construct a graph, it is recommended that you review the Introduction to GraphingPreview the document lab manual. (You are not expected to complete any of the activities in this manual.)

Complete all parts of the Week 4 Lab WorksheetPreview the document and answer all of the questions in the “Lab Questions” section.

Transfer your responses to the lab questions and data tables and your photos from the “Lab Worksheet” into the “Lab Report” by downloading the Lab Report TemplatePreview the document.

Submit your completed “Lab Report” and “Lab Worksheet” through Waypoint.

Carefully review the Grading Rubric (Links to an external site.)Links to an external site. for the criteria that will be used to evaluate your assignment.

ENVIRONMENTAL SCIENCE

GREENHOUSE GASES AND SEA LEVEL RISE

Overview

In this lab, students will carry out several activities aimed at

demonstrating consequences of anthropogenic carbon emissions,

climate change, and sea level rise. To do this, students will first

create a landform model based on a contour map. They will create

models of sea level rise resulting from melting of sea ice and

glacier ice and examine the effects of this potential consequence

of climate change. Students will critically examine the model

systems they used in the experiments.

Outcomes

• Explain the causes of increased carbon emissions and their likely

effect on global climate.

• Discuss positive and negative climate feedback.

• Distinguish between glacial ice melt and oceanic ice melt.

• Construct a three-dimensional model from a two-dimensional

contour map.

• Evaluate and improve a model system.

Time Requirements

Preparation:

Part 1……………………………………………………………….. 5 minutes,

then let sit for 24 hours before starting Activity 1

Part 2 ……………………………………………………………………2 hours

Activity 1: Sea Ice and Sea Level Rise ……………………………..1 hour

Activity 2: Glacier Ice and Sea Level Rise…………………….2.5 hours

2 Carolina Distance Learning

Key

Personal protective

equipment

(PPE)

goggles gloves apron

follow

link to

video

photograph

results and

submit

stopwatch

required

warning corrosion flammable toxic environment health hazard

Made ADA compliant by

NetCentric Technologies using

the CommonLook® software

Table of Contents

2 Overview

2 Outcomes

2 Time Requirements

3 Background

10 Materials

10 Safety

11 Preparation

13 Activity 1

14 Activity 2

15 Submission

15 Disposal and Cleanup

16 Lab Worksheet

18 Lab Questions

Background

For the last 30 years, controversy has

surrounded the ideas of global warming/climate

change. However, the scientific concepts behind

the theory are not new. In the 1820s, Joseph

Fourier was the first to recognize that, given

the earth’s size and distance from the sun,

the planet’s surface temperature should be

considerably cooler than it was. He proposed

several mechanisms to explain why the earth

was warmer than his calculations predicted,

one of which was that the earth’s atmosphere

might act as an insulator. Forty years later,

John Tyndall demonstrated that different

gases have different capacities to absorb

infrared radiation, most notably methane (CH4

),

carbon dioxide (CO2

), and water vapor (H2

O),

all of which are present in the atmosphere. In

1896, Svante Arrhenius developed the first

mathematical model of the effect of increased

CO2

levels on temperature. His model predicted

that a doubling of the amount of CO2

in the

atmosphere would produce a 5–6 °C increase

in temperature globally. Based on the level of

CO2

production in the late 19th century, he

predicted that this change would take place

over thousands of years, if at all. Arrhenius used

Arvid Högbom’s calculations of industrial CO2

emissions in his equations. Högbom thought

that the excess CO2

would be absorbed by the

ocean; others believed that the effect of CO2

was insignificant next to the much larger effect

of water vapor.

It was not until the late 1950s, when the CO2

absorption capacity of the ocean was better

understood and significant increases in CO2

levels (a 10% increase from the 1850s to the

1950s) were being observed by G. S. Callendar,

that Arrhenius’s calculations received renewed

attention.

The Atmosphere

Weather is the condition of the atmosphere in a

given location at a specific time. Climate is the

prevailing weather pattern over a longer period

of time (decades or centuries).

The atmosphere is a thin shell (~100 km) of

gases that envelops the earth. It is made up

principally of nitrogen (78%), oxygen (21%),

and argon (0.9%). Trace gases include methane

(CH4

), ozone (O3

), carbon dioxide (CO2

), carbon

monoxide (CO), and oxides of nitrogen (e.g.,

NO2

) and sulfur (e.g., SO2

) (see Figure 1).

Water vapor is sometimes included in the

composition of gases in the atmosphere, but a

lot of times it is not because its amount varies

widely, from 0%–4%, depending on location.

The concentration of gases in the atmosphere

is not uniform either; the atmosphere consists

of several concentric layers. Some gases are

concentrated at certain altitudes. Water and

continued on next

GREENHOUSE GASES AND SEA LEVEL RISE

Background continued

carbon dioxide are concentrated near the

earth’s surface, for instance, while ozone is

concentrated 20 to 30 kilometers above the

surface. Energy transfer from the sun at and

near the surface of the earth is responsible for

weather and climate. Solar radiation heats land,

the oceans, and atmospheric gases differently,

resulting in the constant transfer of energy

across the globe.

Several factors interact to cause areas of the

earth’s surface and atmosphere to heat at

different rates, a process called differential

heating. The first is the angle at which the sun’s

light hits the earth. When the sun is directly

overhead, as it is at the equator, the light is

direct. Each square mile of incoming sunlight

hits one square mile of the earth. At higher

latitudes, the sun hits at an angle, spreading

the one square mile of sunlight over more of the

earth’s surface. Thus, the intensity of the light

is reduced and the surface does not warm as

quickly (see Figure 2). This causes the tropics,

near the equator, to be warmer and the poles to

be cooler.

Different materials heat and cool at different

rates. Darker surfaces heat faster than lighter

surfaces. Water has a high heat capacity, which

is important on a planet whose surface is 72%

water. Heat capacity is a measure of how

much heat it takes to raise the temperature of

a substance by one degree. The heat capacity

of liquid water is roughly four times that of air.

Water is slow to warm and slow to cool, relative

to land. This also contributes to differential

heating of the earth.

Differential heating causes circulation in the

atmosphere and in the oceans. Warmer fluids

are less dense and rise, leaving behind an area

of low pressure. Air and water move laterally to

distribute the change in pressure. This is critical

in developing prevailing wind patterns and in

cycling nutrients through the ocean.

The Role of the Oceans

The oceans play an important role in regulating

the atmosphere as well. The large volume of the

oceans, combined with the high heat capacity

of water, prevent dramatic temperature swings

in the atmosphere. The relatively large surface

area of the oceans, ~70% of the surface of the

earth, means that the oceans can absorb large

amounts of atmospheric CO2

.

Greenhouse Gases

The greenhouse effect is a natural process;

continued on next page

4 Carolina Distance Learning

Figure 2.

without it, the earth would be significantly cooler

(see Figure 3). The sun emits energy in a broad

range of wavelengths. Most energy from the

sun passes through the atmosphere. Some is

reflected by the atmosphere and some by the

earth’s surface back into space, but much of it

is absorbed by the atmosphere and the earth’s

surface. Absorbed energy is converted into

infrared energy, or heat. Oxygen and nitrogen

allow incoming sunlight and outgoing thermal

infrared energy to pass through. Water vapor,

CO2

, methane, and some trace gases absorb

infrared energy; these are the greenhouse

gases. After absorbing energy, the greenhouse

gases radiate it in all directions, causing the

temperature of the atmosphere and the earth

to rise.

Greenhouse gases that contribute to the

insulation of the earth can be grouped into

two categories: condensable and persistent.

Persistent gases—such as CO2

, methane,

nitrous oxide (N2

O), and ozone (O3

)—exist in

the environment for much longer periods of

time than condensable gases. These times can

range from a few years to thousands of years.

The longer residence allows them to become

well-mixed geographically. The amount of a

condensable gas is temperature dependent.

Water is the primary greenhouse gas in the

atmosphere, but because it is condensable,

it is not considered a forcing factor. Forcing

factors (forcings) are features of the earth’s

climate system that drive climate change; they

may be internal or external to the planet and its

atmosphere. Feedbacks are events that take

place as a result of forcings.

Carbon dioxide, methane, and other gases

identified by Tyndall as having high heat

capacities make up a relatively minor fraction

of the atmosphere, but they have a critical

effect on the temperature of the earth. Without

the naturally occurring greenhouse effect, it is

estimated that the earth’s average temperature

would be approximately –18 °C (0 °F). The

greenhouse effect also acts as a buffer, slowing

both the warming during the day and the cooling

at night. This is an important feature of the

earth’s atmosphere. Without the greenhouse

effect, the temperature would drop below

the freezing point of water and the amount

of water in the atmosphere would plummet,

creating a feedback loop. A feedback loop is

a mechanism that either enhances (positive

continued on next page

www.carolina.com/distancelearning 5

Figure 3.

GREENHOUSE GASES AND SEA LEVEL RISE

Background continued

feedback) or dampens (negative feedback) the

effect that triggers it.

Since the beginning of the Industrial Revolution,

the concentration of CO2

in the atmosphere

has increased from approximately 280 ppm

to 411 ppm (see the Keeling Curve link). This

change is attributed to the burning of fossil

fuels—such as coal, oil, and natural gas—and

changes in land use, i.e., cutting down large

tracts of old-growth forests. Old-growth forests,

like fossil fuels, sequester carbon from the

atmosphere. Burning of either releases that

carbon into the atmosphere in the form of CO2

.

Clearing old-growth forests has an additional

impact on the carbon cycle because trees

actively remove CO2

from the atmosphere to

convert it to sugar and carbohydrates (see

Figure 4). Removing long-lived trees and

replacing them with short-lived crops and

grasses reduces the time over which the carbon

is removed from the atmosphere.

Determining the exact effect that the increase

in CO2

concentrations will have on atmospheric

temperature is complicated by a variety of

interactions and potential feedback loops.

However, the overall impact is an ongoing

temperature increase, known as global climate

change (see Figure 5).

Potential Feedback Loops

Some examples of potential positive feedback

loops that may enhance the effects of global

climate change are:

1. Higher temperatures allow the

atmosphere to absorb more

water. More water vapor in the

atmosphere traps more heat,

further increasing temperature.

2. Melting of sea ice and glaciers,

which are relatively light in

color, to darker bodies or water

decreases the albedo (the

amount of energy reflected

back into space) of the

earth’s surface, increasing

temperatures. Figure 6 shows an

ice albedo feedback loop.

3. Warmer temperatures melt more

of the arctic permafrost (frozen

continued on next page

6 Carolina Distance Learning

Figure 4.

ground), releasing methane into the

atmosphere, further raising temperatures.

4. Higher temperatures may result in greater

rainfall in the North Atlantic, and melting of

sea ice creates a warm surface layer of fresh

water there. This would block formation of

sea ice and disrupt the sinking of cold, salty

water. It may also slow deep oceanic currents

that carry carbon, oxygen, nutrients, and heat

around the globe.

Other factors may work as negative feedbacks,

dampening the effects of global climate change:

1. An increase in CO2

level in the atmosphere

leads to an increase in CO2

in the oceans,

stabilizing CO2

levels.

2. Increased atmospheric temperatures and CO2

promote plant and algae growth, increasing

absorption of CO2

from the atmosphere,

lowering the CO2

levels there, and stabilizing

temperature.

3. Warmer air, carrying more moisture, produces

more snow at high latitudes. This increases

the albedo of the earth’s surface, stabilizing

temperature.

4. Warmer, moister air produces more clouds,

which also increases the albedo of the earth’s

surface, stabilizing temperature.

The relative impact of each of these potential

effects is a subject of debate and leads to the

uncertainty in models used to predict future

climate change resulting from an increase in

anthropogenic (human-caused) greenhouse

gases. However, the consensus among climate

scientists is that the positive feedbacks will likely

overwhelm the negative ones.

Possible Consequences

Consequences of an increase in average

temperature are difficult to predict on a regional

continued on next page

www.carolina.com/distancelearning 7

Figure 6.

Figure 5.

GREENHOUSE GASES AND SEA LEVEL RISE

Background continued

continued on next page

8 Carolina Distance Learning

crop growth. Climes that are more northerly may

experience an increase in productivity. These

shifts will put stress on ecosystems as well. How

resilient each community is to the change will

vary with location and other pressures.

Modeling

The atmosphere and climate are highly complex

systems that are challenging to understand

and predict. To explore such complex systems,

scientists frequently employ models. A model

is a simplification of a complex process that

isolates certain factors likely to be important.

Sometimes a model can be a physical

representation of something too big or too small

to see, such as a model solar system. However,

scientists frequently use mathematical equations

derived from observed data to predict future

conditions. With the addition of computers,

mathematical climate equations can be linked

together in increasingly sophisticated ways to

model multiple factors in three dimensions,

producing global climate models. Because

of computing limitations, some factors must

be simplified. How they are represented within

the model can lead to a degree of error in the

outcome predicted. Ultimately, the quality of

all models is determined by their success in

predicting events that have not yet taken place.

Contour Maps

To determine potential flood risks, scientists,

engineers, and insurance companies use a

number of tools, including historic river flow,

storm tide and rainfall data, hydrological

analysis, and topographic surveys.

scale; some, however, can be predicted with

a relatively high degree of confidence. One

of these is sea level rise. Sea level rise is

the result of two processes. The first is the

melting of glaciers and Antarctic continental

ice. Although the melting of sea ice can have

complex consequences due to the different

densities of salt and fresh water, it will not cause

sea level rise. Melting of glaciers and the deep

ice over the Antarctic continent, however, can.

The second cause of sea level rise, related to

warmer temperatures, is that water expands as

it warms. As the oceans warm, the water rises

farther up the shore. Countries and cities that

have large portions of their land area at or just

above sea level may be in jeopardy.

The loss of mountain glaciers is already

causing changes in freshwater availability.

As glaciers shrink, regions that depend on

seasonal meltwater for hydroelectric power or

for irrigation and drinking water are increasingly

affected. Whereas rainfall may increase in

these regions (even as the amount of snowmelt

decreases), rainwater is considerably more

difficult to control because it does not occur

at as predictable a rate as meltwater. River

systems may be overwhelmed by increased

runoff rates, which can cause flooding. One

of the richest agricultural regions in the world,

California, depends heavily on snowmelt from

the Sierra Nevada. One of the world’s most

populous river valleys, the Indus, is equally

dependent on snowmelt from the Himalayas.

Less predictable consequences are the shifting

of global weather patterns and the subsequent

changes in natural populations. Areas previously

ideal for agriculture may become too arid for

www.carolina.com/distancelearning 9

Topographic surveys can be represented

graphically as maps with contour lines (see

Figure 7). Each contour line represents an

elevation. Figure 7B shows the contour map

from Figure 7A overlaid on the terrain it was

mapped from. Elevations are marked on the map

at set intervals, depending on the scale of the

map. Small-scale maps might have a contour

interval of five feet. Maps of a continent may

have an interval of thousands of feet. All points

connected by a given contour line are at the

same elevation. Depressions in the landscape,

such as craters and basins, are marked with

hatched lines, as seen in Figure 8.

In the following activities, you will be asked

to use a contour map to generate a landform

model. You will use this model to examine the

consequences of sea level rise.

A. B.

Figure 7.

Figure 8.

GREENHOUSE GASES AND SEA LEVEL RISE

Materials

Included in the materials kit:

10 Carolina Distance Learning

Needed from the equipment

kit:

Safety

Wear your safety goggles,

gloves, and lab apron for

the duration of this investigation.

Read all the instructions for these laboratory

activities before beginning. Follow the

instructions closely, and observe established

laboratory safety practices, including the use

of appropriate personal protective equipment

(PPE).

Do not eat, drink, or chew gum while performing

the activities. Wash your hands with soap

and water before and after performing each

activity. Clean the work area with soap and

water after completing the investigation. Keep

pets and children away from lab materials and

equipment.

Modeling

clay, 2 pieces

2 Medicine

cups

Plastic container with lid

Plastic cup

Sharpie® marker

Beaker, 250 mL

Food coloring

Ruler

Reorder Information: Replacement

supplies for the Greenhouse Gases and Sea

Level Rise investigation can be ordered from

Carolina Biological Supply Company, item

number 580802.

Call: 800.334.5551 to order.

Needed but not supplied:

• Blank white paper

• Water

• Printout of page 12

• Freezer

• Salt, 3 tsp

• Scissors

• Pencil

• 2 Coins (dimes or

pennies)

• Timer

• Teaspoon

• Camera (or cell phone

capable of taking

photographs)

Preparation

1. Read through the activities.

2. Obtain all materials.

Part 1: Making Ice

At least 24 hours before beginning Activity 1,

prepare two colored ice cubes:

1. Fill each medicine cup with tap water to the

20-mL mark.

2. Add 5 drops of food coloring to each cup.

3. Remove the lid from the plastic container, and

place the cups on the lid to contain spills.

Place the lid holding the two cups in the

freezer.

4. Allow the mixtures to freeze for at least 24

hours.

Part 2: Building a Model from a Contour Map

1. Print the contour map template (Figure 9,

page 12), and cut out the island represented

along the lowest contour line. This will

eventually serve as the base of the island.

2. Take out one package of clay and knead the

clay to soften it.

3. Using your hand, flatten the clay into a thin

layer.

4. Place the flattened clay on a piece of scrap

paper or a plastic bag to prevent it from

sticking to the work surface, and work or roll

the clay into a thin 2–3 mm layer that is large

www.carolina.com/distancelearning 11

enough to place the cutout on. (Try using the

permanent marker as a rolling pin.)

5. Place the island template on the clay and,

using a pencil, trace around it, cutting into

the clay.

6. Remove the template from the clay.

7. Peel the clay off the work surface and place

the inner, template-shaped piece into the

plastic container. Gently press down on any

ridges formed on the layer by the cutting,

making the layer as flat as possible.

8. Work the remaining clay into a ball.

9. Trim the outer contour off the template.

10. Repeat Steps 3–9 for the second and third

contours, placing each subsequent contour

on top of the previous one, building the

island model.

11. Roll out the fourth layer of clay. Place the

template on the clay and cut the fourth

contour out of the clay. This time, however,

do not place the cutout contour on top

of the previous one, but leave it on your

work space.

12. Trim the paper along the hatched line.

13. Place the ring paper template you just cut

out back down on the clay.

14. Trace the template with a pencil, cutting

Order a Unique Copy of this Paper

Essay Creek is an academic writing service provided to you by, a London-based company.

  • Experience
    Helping students successfully for 11 years.
  • Confidentiality & Security
    Be sure your information will be kept confidential due to our secure service.
  • Quality & Reliability
    8.5 out of 10 average quality score according to our customers' feedback. 97.45% of orders delivered on time.
  • Versatility
    478 active writers in 68 disciplines.
  • 100% money back guarantee
    You can always request a refund if you are not satisfied with the result.

Read more about us

Our team of writers is comprised of people with necessary academic writing skills and experience in various fields of study.

  • Skilled writers only
    We carefully choose writers to employ, paying attention to their skills and abilities.
  • Competence
    Your order will be assigned to a competent writer who specializes in your field of study.
  • In-depth knowledge
    Our writers know both peculiarities of academic writing and paper formatting rules.
  • Motivation
    We keep updated on results our writers show, motivating them to constantly improve their performance.

Read more about our writers

  • Testimonials
    Our clients' testimonials prove we're doing everything right.

Check for yourself

  • Sample essays
    The best way to understand how well our writers do their work is to view sample essays written by them.

View samples

  • Our Free Essay Tools
    Even more opportunities to improve your academic papers.


Bibliography Generator
Words to Pages Converter
Words to Minutes Converter
College GPA Calculator
Thesis statement generator