Most wildfires are naturally occurring and many ecosystems benefit from the natural cycles of forest fires. Burned forests eventually decompose, replenishing the soil with nutrients that allow for new species to grow. Certain plants, such as the Giant Sequoia trees of the Redwood forests, even depend on fires to reproduce. However, man-made changes in Earth’s climate have created hotter and drier fire environments, leading to larger wildfires and longer fire seasons.
What has been your experience with wildfires? Have you or your loved ones ever been affected by wildfires?
Categorize aspects of wildfires into the appropriate sphere.
Particles in the air
Smoke & smog
Dry soil
Trees burned
Animals flee
Polluted water
Atmosphere
Hydrosphere
Geosphere
Biosphere
Identify the 2 spheres interacting in the following examples. Make sure to focus on the items in bold.
Ash may be carried by winds many miles from the fire and then dropped into streams.
Burned plant debris that did not blow away becomes the new soil that can provide some nutrients for new plants
Rainfall over burned land carries ash, soot, and dirt into streams and rivers, changing the turbidity, temperature, and pH.
Smoke and noxious fumes can coat the lungs of animals and people, affecting their ability to breathe.
Learning Target #2: Define negative and positive feedback loops and explain how they are different
Feedback loops help us understand cause and effect relationships. A feedback loop occurs when an action or event leads to a certain result, which then influences the original action or event.
In a positive feedback loop, the effect of an action amplifies the original action, creating a self-reinforcing cycle aka a "vicious cycle"
In a negative feedback loop the effect of an action seeks to stabilize and balance a system or condition aka keep the system in its "happy place"
This image is a model of a negative feedback loop.
Why is this considered a negative feedback loop?
Using the image above to help you, what is one benefit of wildfires?
Scientists have been monitoring changes in global temperatures and the amount of wildfires. Consider the following graph that shows the US surface temperature anomaly (the number of degrees above average) and the acres of land burned each year.
What is the relationship?
As the temperature anomaly increases over time, the number of acres burned
Predict: How could higher temperatures lead to more wildfires?
Consider the following feedback loop:
Which type of feedback loop does this represent?
Justify your answer: Why did you select the type of feedback loop for the previous question? Select 2.
Extend your thinking: What can humans do to reduce the impact of wildfire?
Learning Target #3: Describe the use of models in science and how they can change
Scientists use models to help conceptualize something that may be difficult to understand.
Scientific models change based on new information and technology.
Before watching the video below to learn more about how scientists determined the age of the Earth, make a prediction: How old is the Earth?
Self Assessment: Learning Target #1: Identify Earth's spheres and describe how they interact
Self-Assessment: Learning Target #2: Define negative and positive feedback loops and explain how they are different
Self-Assessment: Learning Target #3: Describe the use of models in science and how they can change
If you struggled with the learning targets, I highly recommend watching these videos.
When half of the parent atoms have become daughter atoms, that's called the half life of that element.
Scientists used radiometric dating on
