Lesson 9 Assessing the Impacts of Climate Change
Risks and Benefits of Human Activity
Are all human activities bad?
Humans need to use energy. We use it to grow, transport, preserve and
cook our food. It heats and lights our homes and moves us to work. It
helps use make everything we need, and the things that we want.
Canada is a northern country that is sparsely populated. We use more energy for transportation of goods and people. We need more energy to heat, and light our homes. Petroleum is used extensively in agriculture to make herbicides, pesticides, fertilizers and fuel, in order to grow food for the whole world. The petroleum industry is important to the Canadian economy and the livelihoods of many people.
Choices we make about energy use need to be balanced with our concerns about the environment. Each choice has advantages, or benefits, and disadvantages or risks. The choices made by people can differ based on their knowledge and perspectives.
Decisions we make about using resources always affect the environment. Wise choices can be very difficult because issues are often complex, but being able to identify peoples perspectives helps us make better decisions.
Canada is a northern country that is sparsely populated. We use more energy for transportation of goods and people. We need more energy to heat, and light our homes. Petroleum is used extensively in agriculture to make herbicides, pesticides, fertilizers and fuel, in order to grow food for the whole world. The petroleum industry is important to the Canadian economy and the livelihoods of many people.
Choices we make about energy use need to be balanced with our concerns about the environment. Each choice has advantages, or benefits, and disadvantages or risks. The choices made by people can differ based on their knowledge and perspectives.
Decisions we make about using resources always affect the environment. Wise choices can be very difficult because issues are often complex, but being able to identify peoples perspectives helps us make better decisions.
Different people with different perspectives will have different opinions on what the risks and benefits of human activities are.
Sean, Megan and Yao need to buy lawn mowers. They are people who care about their community and the environment. They are concerned about climate change. The choice is between gasoline powered, electric (lithium battery) or push mowers. They research the mowers carefully, and make decisions based on their values, and what is practical.
Here is a list of the different perspectives with examples based on the information above:
| Perspective | Focus | Examples of choices and reasons |
|---|---|---|
| scientific | This perspective bases decisions on observations of natural phenomena, development of experiments to determine relationships, and theories. |
Shelli landscapes her yard for low environmental impact as well as beauty. Based on her research, has planted clover instead of grass because it fixes nitrogen and does not require water. According to the articles, she needs a push-mowers to cut the clover without damaging it. |
| technological | This perspective advocates the development of practical uses for scientific discoveries. |
Sean will have solar panels installed next year. He will use the power to run various electric equipment and tool. He will get an electric lawnmower. |
| ecological | This perspective bases decisions on concerns for the environment and balance between biotic and abiotic factors within. |
Protecting the environment is important is of greatest importance to Shelli. She has invested a lot of time to design the most environmentally friendly yard she can have. Making and operating push mowers produce the least environment change. She almost chose an electric mower, like Sean, but making lithium batteries and disposing of them is very hard on the environment. |
| economic | This perspective relates decisions to trade, industry, or money. |
Megan wanted to use solar power like Sean, but her yard is huge. Considering that the electric mower is the most expensive, and the number of solar panels and batteries she would need keep her lawn cut, she just cannot afford it. She will get a gas mower. |
| political | This perspective bases decisions around actions of government or organizations involved with government who attempt to influence the way a country is governed. |
Sean belongs to a group which actively promotes alternate energy sources. It is another reason he chose an electric mower. |
| legal | This perspective bases decisions on existing laws or their interpretations. |
Shelli often works late, and has to do her yard work in the evening. There is a noise bi-law in her town that would prevent the use of a gas power mower after 7 pm. It is another reason she chose a push mower. |
| ethical | This perspective bases decisions around the accepted beliefs of what is right or wrong within different groups of people. | Megan knows that using a gas mower is not the most environmentally friendly, but she recognizes that in her community of small farm producers, weed control is an important issue. A gas mower enables her to effectively keep weeds under control so they do not spread to the neighbors farms. In spite of her environmental concerns, a gas mower just seemed like the right thing to do. |
| societal | This perspective focuses on ways that society functions and the way people interact and carry out their lives. |
Shelli knows that water conservation is an issue in her community. She give much of the food that she produces in her yard to the local food bank. Her clover lawn helps her contribute to her community. |
These examples show some of the perspectives considered about one human activity. They are not all the perspectives.
The issue of climate change is much more complex than the issue of choosing a lawn mower.
In Canada, about 19% of energy use in a home is for heating water. If you were building a new home, or updating the water system in your home, which system would you choose? Assess each system. Identify several risks and benefits, and give the perspective that it represents. Use the information below.
Most Albertans use natural gas
to heat their water, so the initial cost of setting up a system is moderate. Gas heaters tend to last 10 - 15 years. They are less
efficient that electric heaters, but the energy waste just heats the
home... so is it really waste?
Natural gas is abundant and cheap in Alberta. It is a local resource that relies on local business.
Gas heaters do emit CO2. Natural gas is methane, which is a powerful greenhouse gas. Some gas escapes in production.
Repairs to hot water heaters topically need to be done by technicians.
| Benefits | Risks | Perspective |
|---|---|---|
| moderate installation price and energy is inexpensive (now) | economic | |
| produces greenhouse gases | environmental / ethical | |
| local resource and supports local business. | social | |
| technician needed for installation and repairs | technological | |
Courtesy Wikimedia
Electric hot water heating is becoming more common because regulations make it necessary in high density housing. Up to 60% of new homes are heated electrically.
The initial installation cost is higher, and the energy cost is higher. Some maintenance is required, but a technician is not required.
There are no greenhouse gases produced in the home, but keep in mind that in Alberta about 87% of electricity is generated using coal and natural gas, and only about 13 percent comes from sustainable sources like hydroelectric.
Electric heaters are more efficient. Electric heating might be at the source (for example, under the sink), and can be part of a smart home, so water begins heating on a schedule or as you enter a room.
| Benefits | Risks | Perspective |
|---|---|---|
| high installation cost. energy more expensive. | economic | |
| less greenhouse gases produced | environmental | |
| necessary by regulations in high density housing | legal | |
| more efficient | technological | |
| greater flexibility: water-on-demand and smart home features. | social |
Courtesy of Wikimedia
Solar heating is the most expensive to install, but the energy is free.
No greenhouse gases are produced while running the system.
The system does require the most maintenance. It is not yet proven technology in the cold Alberta climate.
It is not a stand alone system, meaning a gas or electric system is needed when there is not sunlight.
Simple solar heating systems are used to heat pools in the summer.
| Benefits | Risks | Perspective |
|---|---|---|
| Expensive to install | economic | |
| almost free to operate cost of energy is small | economic | |
| some maintenance required | social | |
| Produces no greenhouse gases while operating | environmental / ethical | |
| In most cases requires a secondary system | economic / environmental | |
| technology is not yet proven in a cold climate | technological |
Courtesy of Wikimedia
This is a simplistic look at a human activity - heating water. The
questions asked by environmental engineers go far deeper. for example, what is the environment affect of mining needed to supply the metal parts for gas or electric heaters? Are solar water heaters locally made? What is the affect of transporting them from distant places? What is the effect of disposing of these three kinds of heaters?
Any real analysis of human activities can become very complex and mathematical.
Any real analysis of human activities can become very complex and mathematical.