Handout 1A: Benefits of Hydraulic Fracturing

Transcription

1 Handout 1A: Benefits of Hydraulic Fracturing Directions: Read the information and consider the associated questions, as you will need to explain your answers. What is fracking? Hydraulic fracturing, or fracking is a process by which natural gas and oil are extracted from bed rock by opening and widening fractures below the earth s surface by injecting a mixture of water, chemicals, and silica sand at high pressure into drilled wells in the earth. Though the procedure has been around since the late 1940 s, it is only recently that modern drilling techniques have made this process an economical method to harvest these resources. The recent more widespread use of this technique, along with the use of natural gas deposits in the United States, has led to increased awareness of fracking. There are a number of benefits associated with hydraulic fracturing. These include: Providing energy to meet the needs of the U.S. population. Natural gas is one of the most widely used fuel sources in this country, and accounts for roughly 25% of the nation s fuel sources. Thanks to modern fracking techniques, this resource is much more widely available, and we now have enough fuel for nearly 100 years without importing any natural gas, reducing our dependence on foreign fuel imports. Providing cleaner burning fuel. Natural gas that is extracted through the use of hydraulic fracturing is a cleaner-burning fuel than either coal or petroleum, resulting in fewer emissions of pollutants and CO 2. This means that there are fewer greenhouse gases put into the air. Also, hydraulic fracturing requires fewer drilling sites and wells than other methods, meaning that less area is needed to remove natural gas from the environment. Cheaper fuel and plenty of jobs. Due to the fact that modern fracking techniques have made it possible to efficiently extract more natural gas product domestically, the cost of natural gas has decreased. This savings has been passed onto the consumer, meaning people pay less for energy. In addition, the hydraulic fracturing industry has created thousands of jobs, contributing to local and national economies. 1. If you had only the information above, would you support fracking? Why or why not? 2. In what ways did the the.news clip support the information in this handout? 3. In what ways did the the.news clip not support the information in this handout? 11

2 Handout 1B: Dangers of Hydraulic Fracturing Directions: Read the information and answer the associated questions. What is fracking? Hydraulic fracturing, or fracking is a process by which natural gas and oil are extracted from bed rock by opening and widening fractures below the earth s surface by injecting a mixture of water, chemicals, and silica sand at high pressure into drilled wells in the earth. Though the procedure has been around since the late 1940 s, it is only recently that modern drilling techniques have made this process an economical method to harvest these resources. The recent more widespread use of this technique, along with the use of natural gas deposits in the United States, has led to increased awareness of fracking. There are a number of drawbacks associated with hydraulic fracturing. These include: Environmental risks. There are a number of environmental concerns related to hydraulic fracturing. One concern is simply the amount of water it takes to extract these resources it could involve millions of gallons of water! In drought prone areas of the country, this could create additional strain on the environment. The chemicals involved in the process are also a danger. If spilled or mismanaged, these could seep into ground water and local drinking water. The wastewater produced by fracking is also hazardous and must be disposed of properly so it does not contaminate the local environment. Finally, the process of fracking itself, along with disposing wastewater (which is usually injected into deep wells) actually causes small earthquakes to occur in the vicinity. Human and animal health risks. The hazardous materials used in the fracking industry can seriously harm people living near these sites. If the chemicals used in the process are not managed properly, or there are leaks in the well and other incidents, these chemicals can end up in drinking water. People living nearby some of these sites have reported illnesses such as headaches, dizziness, liver and intestinal damage, and even cancer. Livestock on nearby farms, as well as fish in neighboring waterways have died near some sites. Additionally, inhaling silica sand, which is used in the fracking process, is associated with a respiratory disease, Silicosis, which is associated with swelling in the lungs and difficulty breathing. 1. If you had only the information above, would you support fracking? Why or why not? 2. In what ways did the the.news clip support the information in this handout? 3. In what ways did the the.news clip not support the information in this handout? 12

3 Handout 2: Correlation or Causation? Directions: Read the information and answer the associated questions. When two variables are related to one another, they are correlated. If the correlation is positive, then one as one variable increases, so does the other. An example of a positive correlation is temperature and ice cream sales. 1. What is another example of a positive correlation? As temperature increases, ice cream sales also increase. If the correlation is negative, then as one variable increases, the other decreases. An example of a negative correlation is temperature and heating bills. As temperature increases, heating bills decrease. 2. What is another example of a negative correlation? However, correlation does not imply that one of the variables caused the other variable to occur. Consider the following example: As ice cream sales increase, crime also increases. Does this mean that ice cream causes criminal activity? Or, that crime causes people to eat ice cream? 13

4 This is an example of a spurious relationship. This is a correlation between two variables that does not result from any direct relation between them but from their relation to other variables. Ice cream sales and crime are both related to increasing temperatures. As temperature rises, so do both ice cream sales and crime. 3. Can you think of any other spurious relationships? (These are variables that appear to be related, but are actually both related to a third variable). So how do we determine causation? One way that we can help understand cause and effect is through a controlled experiment. In a traditional experiment, scientists are able to control the variables. For example, if you were studying the effects of various amounts of sunlight on the growth of plants, you would have several identical plants that were exposed to different amounts of sunlight. By controlling the initial size of the plants, the soil, water, and temperature (all variables that could impact plant growth), you could determine that sunlight was the variable that impacted the relative size of the plants after the intervention. In other words, if all other variables are equal, then sunlight is likely the cause of the plants relative sizes. When using the experimental method, researchers are able to manipulate the independent variable (sunlight) in order to determine the effects upon the dependent variable (plant growth). In the real world, controlling these variables is more difficult. There are a number of extraneous variables. These are variables that influence the outcome of an experiment, though they are not the variables that are actually of interest. For example, suppose in the previous experiment, the research forgot to control for the amount of water given to the plants, so as a result, some plants got more water than others. Is it possible to say that the only reason that some plants were larger than others was due to sunlight? In this case, we could not be sure, because the amount of water given is an extraneous variable. 14

5 Key Vocabulary: Correlation: An association or relationship between two variables. Experimental method: A study in which the investigator manipulates at least one variable (the independent variable) to determine if this causes changes in at least one other (dependent) variable. Extraneous variables: These are variables that influence the outcome of an experiment, though they are not the variables that are actually of interest. Independent and dependent variables: The independent variable (IV) is that which is manipulated and/or controlled by the researcher, while the dependent variable (DV) is the response that is measured. (For example, if studying the effects of various levels of sunlight exposure on houseplants, the IV would be the amount of sunlight the plants received; the DV would be the observations and/or measurements of the plants after receiving different light treatments). Spurious relationship: A correlation between two variables that does not result from any direct relation between them but from their relation to other variables. *Graphics used are public domain images from OpenClipArt. 15