GEOB102

GEOB 102 Our Changing Environment : Climate and Ecosystems Lab 1

1

Lab 1 - Energy and Climate Change

Due: Friday, 2nd October 2020 11:59 pm PT

Objectives:

● Understand all components in the surface radiation budget

● Identify environmental variables that affect components in the radiation budget

● Calculate net radiation and albedo

● Explain annual patterns and trends in atmospheric CO2 concentrations

● Explain the concept of a carbon footprint and the factors that contribute to it

Total marks: 26

Introduction

Read the lab carefully. Content included in this assignment covers Friday, Week 1 to Monday, Week

4 (inclusive). Your textbook (chapters are listed under the Course Schedule on Canvas) and lectures

will provide the required background. All answers should be filled out in Canvas. We recommend

that you download this handout, create responses in a word doc or on paper, then fill in answers

online. Please double-check your answers on Canvas before submitting! Provide answers to TWO

decimal places where appropriate (Canvas will not accept units, so you may omit these from your

answers). While you may use any spreadsheet program (Microsoft Excel, Open Office, Google

Sheets), we recommend Excel, free to all UBC students via the student software site.

PART 1: Daily Radiation Budget [12 marks]

We will be using the SURFRAD network website to access radiation data from 2 monitoring sites in

the United States. The network provides long-term, continuous measurements of the surface radiation

budget for multiple sites, and available data includes incoming and reflected shortwave radiation,

incoming and outgoing longwave radiation and net radiation. This data can be downloaded and used

to inform climate research. Also available on the website are photographs of the sites, which can be

used to gain insight on radiation budgets.

Firstly, follow the instructions in the document: Accessing the SURFRAD network. This document,

which is on the main assignment page in Canvas, will show you how to obtain the data and graphs

needed to complete the following questions.

Note: For date selection in step 3, choose the date following date which applies to you (based on the

last 2 digits of your student number):

0-25 : June 01 2019

26-50 : July 05 2018

51-75 : May 28 2018

76-99 : August 05 2019

GEOB 102 Our Changing Environment : Climate and Ecosystems Lab 1

2

Fort Peck, MT

Q1. (upload a screenshot of the graph, acquired by following the above instructions (Accessing the

SURFRAD dataset), to canvas)

Answer the following questions for the graph of Fort Peck, MT:

Q2. Name 2 variables that could affect the value of SW ↓ and SW ↑. [2]

Q3. Why do SW ↓ and SW ↑ have similar (if not the same) values between 3 and 11 UTC? [1]

Q4. Why is LW ↑ greater than LW ↓? [1]

Q5. Describe the diurnal pattern of total net radiation (Q*), and state which component of the

radiation budget exerts the most control over Q*. [2]

Desert Rock, MV

Q6. (upload a screenshot of graph, acquired by following the above instructions (Accessing the SURFRAD dataset), to canvas)

Q7. State 2 differences between the two sites and suggest some reasons for these differences in terms

of climate and environment. [2]

Calculating albedo and net radiation (see more in the endnotes)

1. Download the Fort Peck radiation data spreadsheet containing radiation data for a day in July in Fort Peck. Fill in the columns for albedo and net radiation using the following

equations:

Net radiation (𝑸 ∗) = (𝐾 ↓ + 𝐿 ↓) – (𝐿 ↑ + 𝐾 ↑) = (𝐾 ↓ − 𝐾 ↑) + (𝐿 ↓ − 𝐿 ↑) (1)

The albedo or reflectivity (α) of a surface refers to the proportion of incident short-wave radiation

which is reflected by the surface:

Albedo (α) = 𝐾↑

𝐾↓ (2)

Q8. At what time of day does the maximum Q* occur? [1]

Q9. What is the value of albedo at 0900 and 1700 hours? Express answers in percentages (e.g. 10%

not 0.1). Explain how albedo changes between these hours. [3]

GEOB 102 Our Changing Environment : Climate and Ecosystems Lab 1

3

PART 2: CO2, Temperature, and Climate Change [12 marks]

There is a growing body of evidence and data on the issue of climate change. Some of this is outlined

in Chapter 7 of your textbook. You will need to refer to the endnotes at the end of this document for

help with some of the questions.

Examine the updated version at the end of this document (in endnotes; Fig. 2), downloaded from the

NOAA web-site: https://www.esrl.noaa.gov/gmd/ccgg/trends/. This famous graph is often referred to

as the “Keeling Curve” after the name of first author who originally published the data. It represents

atmospheric CO2 concentration atop Mauna Loa, Hawaii (in parts per million, ppm).

Q10. List 4 processes/activities that are responsible for the peaks and troughs observed in the keeling

curve (2 for each). [1]

Click on the “data” tab in the NOAA web-site listed above to get the files with the annual mean data

(“Mauna Loa CO2 annual mean data” in ppm or parts per million) and the annual growth rate data

(“Mauna Loa CO2 annual mean growth rates”; represents change in CO2 from one year to the next,

reported as ppm/year). Click on ‘CSV’ next to the file name to download. Familiarize yourself with

these two tables.

Q11. Find the most recent annual mean atmospheric CO2 concentration at Mauna Loa (i.e., for

2019). By what percent has the atmospheric CO2 concentration increased from the pre-industrial value

of 280 ppm? [1]

Q12. Watch the film at: https://www.esrl.noaa.gov/gmd/ccgg/trends/history.html. Focusing on the

data shown on the left figure (snapshot, below) from about 0-2 minutes of the film, explain what is

being portrayed. Also: Can you explain why there is so much more variation in values at latitudes

30°N and higher than those south of the equator? See clock to the right of the graph for year and

month – you may need to play the film a couple of times to become familiar with the trends) [2]

GEOB 102 Our Changing Environment : Climate and Ecosystems Lab 1

4

Q13. Examination of data used to compute the climate change index:

Download the dataset in the climate change index spreadsheet. This table presents the following data

for the time period 2006-2019: 1) Global average temperature, 2) Atmospheric CO2 concentration, 3)

Global Mean Sea Level (mm height with reference to a fixed datum), 4) Average Arctic Sea Ice

Extent. These variables are critical indicators of human impact on climate and affected systems. The

variables are used to compute the Climate Change Index, a single number calculated annually that can

be used to show accumulated change over time. Here, we will ignore the index and examine the data

it derives from.

Open the Excel spreadsheet. Create time-series (line) graphs to illustrate the variables. Because the

variables are measured on different numerical scales, I suggest you either construct: i) four separate

line graphs, one for each variable, or ii) three graphs, the first with CO2; the second with Global Mean Sea Level, and the third with Global Avg. Temp. and Average. Arctic Sea Ice Extent.

Your TA will help you with the “line graph” feature in Excel. For general graphing instructions, refer

to the handout on Constructing Line Graphs (posted in Canvas) or consult your TA in lab. Note that:

if you choose option ii), you will have a secondary y-axis on the last graph: one, on the left for the

first variable (e.g., Global avg. temp.), the second on the right, for the other variable, e.g., Average.

Arctic sea ice extent (e.g., see Fig. 1 below). Remember, time is always your x-axis variable in a time- series graph. The following Excel help tutorial will help with adding secondary y-axes:

https://www.youtube.com/watch?v=P-mB4I16GC8

1st Y-axis 2nd Y-axis

Fig 1: Example of graph with secondary y-axis. Accessed from:

https://www.youtube.com/watch?v=viD-WVEK_s0

Present your graphs together (e.g., side by side; one on top of the other) so you can easily compare

trends among the variables. Be sure to include a title, axis labels indicating units of measurement and,

if you have more than one series per graph, a legend to indicate which is which. Place the graphs

(copy and paste each) into a Word document and convert to pdf. If you are unable to convert to pdf,

you may submit your Word doc. Follow the prompts (click ‘browse computer’, select your file, etc.)

to attach to the electronic submission in Canvas. [3]

Q14. Looking at sea surface height change (represents change relative to the 1993-2008 average),

comment on the pattern over time (direction, magnitude, variability)? How are sea surface height

GEOB 102 Our Changing Environment : Climate and Ecosystems Lab 1

5

trends related to the other 3 variables, if at all? Explain any relationships in terms of underlying

processes of cause-effect [2]. You may be interested to view the animation at:

https://climate.nasa.gov/news/2614/25-years-of-global-sea-level-data-and-counting/

Q15. Calculate the percent change in temperature that occurred between an earlier year and the last

year in the time sequence, as follows (you will compute this using 2 different ‘earlier’ years) [1]:

2006 to 2019 ____

2014 to 2019 ____

Q16. Is comparing the percentage of change between individual years a good way to assess temporal

trends in the variable temperature? Why/why not? What would be a better temporal scale for this

variable? [2]

PART 3: What is your impact? Carbon footprint: [2 marks]

Estimate your carbon footprint. This is similar to an ecological footprint (see endnotes), but converted

to units of CO2 you release per unit time (in tons/year) and is your contribution to carbon emissions.

To do this, access one of the leading carbon calculators such as the Cool Climate Network’s:

https://coolclimate.berkeley.edu/calculator, (see Appendix “Using the Calculator”) or Conservation

International’s: https://www.conservation.org/act/carboncalculator/calculate-your-carbon-

footprint.aspx#/

Note: Both of these tools are American. You may need to mentally convert your travel into US units

(miles from kilometres) or other units. You may simply estimate – you want rough but representative

numbers. Also: Please visit the site as soon as you can – it may become overloaded as students access

it, and you may need to return to it at a later time.

Q17. Carbon footprint: [1]

Q18. Justify your answer by providing details of, e.g., indicate those elements of your lifestyle that

are particularly carbon-hungry; those that are relatively conservative of energy/carbon, etc. You will

not be judged for this. Some of us have taken more than our share of international flights; or drive

SUV’s! [1]

REFERENCES

Arbogast et al. 2018 (course text) Or: either of the following references in lieu:

Christopherson, et al. 2015. Geosystems, (any Canadian Edition), Pearson.

Strahler and Archibold 2011 Physical Geography: Science and Systems of the Human

Environment (any edition). Hoboken, NJ: John Wiley & Sons Inc.

Endnotes

Part 1:

The surplus or deficit of radiant energy that may exist at a given place or time can be obtained by

calculating the net radiation budget – the difference between total incoming and total outgoing

GEOB 102 Our Changing Environment : Climate and Ecosystems Lab 1

6

radiation. The terms short-wave and long-wave radiation refers to radiation from the sun (short-wave)

and radiation from the Earth and atmosphere (long-waves).

The net radiation, Q*, may be positive, negative, or zero. When the surface is gaining more radiant

energy than it is losing, Q* is positive, indicating the potential for warming.

A negative Q* implies the surface is losing energy, indicating the potential for cooling.

Q* may be determined from the radiation balance equation:

Q* = (K↓ + L↓) – (L↑ + K↑) = (K↓ - K↑) + (L↓ - L↑), where

K↓ = incoming short-wave radiation from the Sun K↑ = short-wave radiation reflected by the surface L↓ = incoming long-wave radiation emitted by the atmosphere L↑ = out-going long-wave radiation emitted by the surface

The albedo or reflectivity (α) of a surface refers to the proportion of incident short-wave radiation

which is reflected by the surface:

α = K↑/ K↓

Part 2:

Keeling curve: https://www.esrl.noaa.gov/gmd/ccgg/trends/, accessed August 07, 2020.

Fig 2. Keeling curve. Accessed August 2020

Part 3:

Ecological footprint concept: This was derived in the 1980’s by UBC professor Dr. William Rees to

characterize the impact on environment that a single person or entity makes. The World Wildlife

Fund define it as simply “the amount of the environment necessary to produce the goods and services

necessary to support a particular lifestyle” (http://wwf.panda.org/).

GEOB 102 Our Changing Environment : Climate and Ecosystems Lab 1

7

Using the calculator

● Change Miles to KM in settings ○ Click on settings (this can be found on the right hand of the site) ○ Click “Switch to metric units” underneath the Assumption Values box

● Hold on to your results! ○ The browser will save your data, however there’s potential for your results to get lost.

We recommend taking a screen shot or documenting them manually

○ Your initial results will be important to compare with yur final results and be used for our final discussion

● Necessary details for the calculation: ○ Heating oil and other fuels…$0.13 per kWh ○ Natural gas…………………$0.10 per kWh