Chapter 1. Science Literacy and the Process of Science

Introduction

Welcome to the Interactive Study Guide for Chapter 2 of Environmental Science for a Changing World! This Study Guide will help you master your understanding of the chapter's Guiding Questions, using interactive Infographics and activities, as well as targeted assessment questions. Click "Next" to get started, or select a Guided Question from the drop-down menu to the right.

GUIDING QUESTIONS

• What kinds of questions are under the purview of science and why is science limited in this way? Why do we say science is a “process” and that conclusions are always tentative (nothing is ever proven)?
• How are scientific hypotheses generated and tested? What are the two main types of scientific studies and why do we need both types?
• Why is ozone in the stratosphere beneficial to life on Earth and how is it being depleted? What is the evidence that ozone depletion might be harmful to the health of humans or other organisms?
• How did scientists use the process of science to help us understand what was happening with the ozone layer and what unknowns still exist?
• How did scientists, policy makers, and world leaders take the science about ozone depletion and turn it into policy?

[NOTE: this Study Guide is intended for demo purposes only, and has not yet been fully QA'd]

Guiding Question 2.1: Why do we say science is a “process”…

Why You Should Care

You can be certain that scientists are never certain—because the scientific method never proves anything with 100% certainty. This can cause confusion with non-scientists who want definite answers. Adding to the confusion is the fact that scientists use the term ‘theory’ completely differently than the general public. Understanding the process of science and its limitations will help you better understand and interpret scientific evidence.

What kinds of enquiry, process, and knowledge are considered ‘science’? Which two blocks on the infographic below indicate where science happens?

Infographic 2.2 Certainty in Science

Guiding Question 2.2: How are scientific hypotheses generated and tested…

Why You Should Care

Understanding how scientists form and test hypotheses will help you understand scientific information in your daily life. Whenever you watch the news and hear that Food X causes cancer, you shouldn’t accept that as fact. Instead you should consider the science behind the news story. A group of scientists must have suspected that Food X might cause cancer and tested this hypothesis. But what kind of study did they eventually use? What if the findings by the scientists were from a completely observational study, such as a survey to determine how many cancer patients consumed large amounts of Food X? If this were the case, then only a connection between cancer and Food X can be made. It would take an experiment for the researchers to claim that Food X causes cancer.

To complete the activity below, click on a label at the bottom, then click the question mark icon on the Infographic where it belongs.

Infographic 2.3

Guiding Question 2.2 (continued)

Infographic 2.5

Guiding Question 2.3: Why is ozone in the stratosphere beneficial to life on Earth…

Why You Should Care

Because Ultraviolet radiation has more energy than visible light, it can cause chemical changes in some molecules; sun fading, for example happens because UV can break down pigment molecules. UV can also affect biological molecules like proteins and DNA. Suntans, in fact, are the body’s response to excessive genetic damage from UV exposure. Sunscreens work by absorbing UV before it can cause damage to skin cells.

Just like sunscreen, ozone in the stratosphere can absorb the energy from UV and dissipate it before it reaches the earth. The depletion of ozone from its interaction with human-made CFCs is cause for concern because it is allowing more UV to pass through. Since the genetic damage UV causes may lead to cancer, there is concern that rates of skin cancer will increase globally.

Infographic 2.1 The Atmosphere and UV Radiation

Guiding Question 2.3 (continued)

Guiding Question 2.4: How did scientists use the process of science…

Why You Should Care

By now you’ve probably noticed that the overarching theme of this chapter is what science does and doesn’t do. While it’s important to know that science never answers a question with 100% certainty and for every question answered a new one is asked, that doesn’t mean that scientific findings can’t be used to improve our lives.

Infographic 2.7

Guiding Question 2.5: How did scientists, policy makers, and world leaders…

Why You Should Care

As with experts in any field, scientists often have a difficult time getting non-experts to understand the value and implications of their findings. The Montréal Protocol is one of the best examples of scientists succeeding at using evidence to lead to policy changes that are helping a negative situation.

Infographic 2.6

Short-Answer Questions

Similar to the findings that CFCs released by human activity into the atmosphere coincided with depletion of the ozone layer, atmospheric scientists have also discovered a relationship between the human release of so-called ‘greenhouse gases’, like carbon dioxide and methane, and an average increase in global temperature. Like the Montréal Protocol, the Kyoto Protocol was an international compact to reduce emissions of these gases, but unlike the Montréal Protocol, it was never ratified by enough countries to make it a viable agreement.