3/31/15

Tonight's homework is to complete Assignment 64 (#5 can be ignored for now). Additionally, it is strongly recommended to look over Chapter 21 in Botkin and Keller to help fill in any gaps in knowledge. Your exam grade is present on PupilPath and you will be receiving it back tomorrow in class. If you are unhappy with your score, then time for exam corrections will be available on Wednesday and Thursday after school.

3/30/15

Tonight's homework is to complete Assignment 63 and read 21.3 from Botkin and Keller.

Assignment 63 Understanding Ozone and Ozone Depletion

Answer all of the following questions to the best of your ability.

1. Which of the following statements is most accurate?

A. Ozone near the surface of Earth protects us from ultraviolet radiation.

B. Ozone in the stratosphere protects us from harmful radiation from the Sun.

C. Exposure to ozone increases one’s risk of skin cancer.

D. Ozone is added to the atmosphere by fossil fuels.

E. Ozone can form in the deep ocean.

2. What role do chlorofluorocarbons play in the environment?

A. They add ozone to the troposphere.          D. They lead to the depletion of stratospheric ozone.

B. They add ozone to the stratosphere.          E. They no longer pose a threat to the environment.

C. They lead to the depletion of ground-level ozone.

3. The type(s) of ultraviolet radiation most strongly absorbed by ozone in the stratosphere would be

A. UVA.                                                            D. UVB and UVC.

B. UVB.                                                            E. UVA and UVB.

C. UVC.

Free Response Practice

4. In the mid 1970s, Sherwood Rowland and Mario Molina predicted a thinning of the stratospheric ozone layer over Antarctica. The thinning was confirmed in the late twentieth century and has continued into the twenty-first century.

a. Identify the class of chemical compounds that is primarily responsible for the thinning of the stratospheric ozone layer and describe TWO major uses for which these chemicals were manufactured.

b. Describe how the chemical compounds that you identified in part a. destroy stratospheric ozone molecules. You may include chemical equations as part of your answer.

c. Identify the major environmental consequence of the depletion of stratospheric ozone and describe TWO effects on ecosystems and/or human health that can result.

d. Ozone formed at ground level is a harmful pollutant. Describe TWO effects that ground-level ozone can have on ecosystems and/or human health.

3/26/15 and 3/27/15

This weekend's homework is to complete Assignment 62. There will be a check-in tomorrow regarding our discussions of climate change thus far. Also, you should read this (and the associated pages) or 20.5 (How We Study Climate) in Botkin and Keller.

Remember that the APES review session will be held at the Museum School from 9:00 to 3:00 on Saturday.

Resources from today
Today's Powerpoint about what to do about climate change

3/25/15

Tonight's homework is to complete Assignment 61.

Resources
Powerpoint presentation from class today

3/24/15 and Mock Exam Resources

Tonight's homework is to review the mock exam and produce a study aid (ex. review sheet, flash cards, etc.). You should bring this study aid to class tomorrow. Below are several resources to aid you in this process.

Here are a few ideas:
- look at the questions related to pollution and climate change (especially those you may have gotten incorrect) and make flash cards/a review sheet with the terms and definitions
- focus on the questions about old material

Mock Exam Multiple Choice Key

Mock Exam Multiple Choice Answers + Explanations - this could be pretty helpful! It's got the questions, the answers, an explanation of why the answer is what it is, along with which unit/topic the question is aligned with, and what proportion of students in 2008 got it right

Free Response Scoring Guide - also very useful - just saying.

FRQ Scoring Commentary (i.e. what students did well/messed up in 2008)

FRQ #1 Sample Student Responses

FRQ #2 Sample Student Responses

FRQ #3 Sample Student Responses

FRQ #4 Sample Student Responses

3/23/15

Tonight's homework is to complete Assignment 60 (hypothesis, graph, and data analysis). Tomorrow we will go over the Mock Exam.

Assignment 60 - Investigating the Effects of a Greenhouse Gas

Introduction

Global climate change is defined as changes in any aspects of the Earth’s climate, including temperature, precipitation, and storm intensity and patterns. This activity will focus on one of those variables: temperature.

Global average temperature has fluctuated over the past 4.7 billion years. Over the past 900,000 years, the troposphere has experienced prolonged periods of global cooling and global warming. Such periods can be caused by a number of factors:

•       Changes in the length of Earth’s elliptical orbit around the Sun every 100,000 years.

•       Changes in the tilt of the Earth’s axis as it rotates around the Sun every 40,000 years.

•       The direction of the tilt of Earth’s axis wobbles with a period of 26,000 years.

•       Changes in outputs of energy by the Sun related to 11-year sunspot and 22-year solar magnetic cycles.

•       Large volcanic eruptions.

•       Changes in levels of greenhouse gases in the troposphere.

The greenhouse effect is a natural process that warms the Earth’s lower troposphere and surface because of greenhouse gases. These gases trap heat reradiated from Earth’s surface and are essential to keep the global average temperature high enough to sustain life. Greenhouse gases include water vapor, carbon dioxide, methane, and nitrous oxide. While these gases have been present in the troposphere throughout Earth’s history, their concentrations have significantly increased since the Industrial Revolution. These increases result from burning fossil fuels, clearing and burning forests, and planting rice and using inorganic fertilizers. Global warming is a warming of the Earth’s atmosphere because of increases in the concentration of one or more greenhouse gases.

Today we are going to investigate the effects of carbon dioxide on a surface’s ability to retain heat.

“Investigating the Effects of a Greenhouse Gas” Analysis Questions

Answer all of the following questions to the best of your ability in complete sentences.

1. Form a hypothesis. How do you think the temperature change will be different when the container is filled with added carbon dioxide compared to when it is filled with just air?

2. Thoroughly analyze your data. This means that you should:

·         Graph your data

·         Make inferences and evaluate your hypothesis

·         Support your conclusions by referring to your data

·         Try to explain what happened 

Resources from Today's Class
Climate change presentation from class today

11BD

Time (minutes)	Temp. (◦C) – added CO2	Temp. (◦C) – no added CO2	Concentration CO2 (ppm) – added CO2	Concentration CO2 (ppm) – no added CO2
0	23	26
5	33	40
10	38	42	1250	1225
15	34	37	9950	1150
20	31	30	9406	1111
25	28	27	6400	1098

12BD

Time (minutes)	Temp. (◦C) – added CO2	Temp. (◦C) – no added CO2	Concentration CO2 (ppm) – added CO2	Concentration CO2 (ppm) – no added CO2
0	53	56	1815	1575
5	40	56	7542	1647
10	32	39	2745	1495
15	29	33	2240	1543
20	28	31	1943	1572

3/20/15

Thank you for your hard work on the mock exam and the energy exam. Your only homework is to finish reading Chapter 20 in the textbook (and the article from class today if you somehow did not/could not do that).

ONE FAVOR TO ASK THOUGH: I need your mock exam Scantrons back. Please bring them with you to class on Monday. Thank you.

And it may look a little dark right now for Wheltonian Democracy. Maybe Iowa State wasn't a strong bet. But just you wait. Just. You. Wait.