The Changing Earth: How We Prepare, Survive and Respond to Earth’s Forces
How Does The Earth Change Over Geologic Time?
MINDS ON
Every time a natural process operates or a natural hazard occurs, the Earth has changed in some way. The collection of these events across the globe causes a slow transition from the present familiar form of Earth to a new version of itself. This ever-changing Earth requires us to re-evaluate our behaviour, strategies and actions. What was once acceptable practice can prove to be no longer sustainable. The best and most current example of this is climate change. Under a previously more stable climate system, human civilization organized itself to exist in those conditions. However, with a rapidly changing system come the pains of “living in and preparing for the past.”
Responding to Environmental Change
Explore the statements below and form a response to how each of these local-international human practices must change with our changing Earth.
Download a digital version of this table and fill it in.
Consider the following Success Criterion:
| Statement | How Can Humans Respond to this Environmental Change? |
|---|---|
| Since the Industrial Revolution in the 1750s, greenhouse gas emissions from industry and transportation have risen, altering the energy balance of the Earth’s atmosphere and increasing global temperatures. | |
| Since the beginning of human civilization, settlement has been heavily concentrated along coastlines, rivers, and shorelines. Historically, few concerns (except the odd hurricane/storm surge) were associated with this practice, but coastal communities are currently experiencing more frequent intense cyclones and must deal with sea level rise. In combination, sea level rise and intensifying storms make the settlement of coastal areas a less sustainable decision. | |
| The city of Calgary is built on the banks of the Bow River, which historically experienced rare flood events. A changing climate is affecting spring flow rates of the river, increasing the risk of regular flooding, and driving up the cost of insurance along the floodplain. | |
| Many of the world’s largest rivers are fed by melting continental glaciers. A changing climate is shrinking their size and reducing their flow rates to the level where billions of people living along their courses experience reduced access to water. At current rates, these glaciers will disappear along with the only source of water for many people. |
ACTION
Climate change is a great example of the global connection between people and a changing planet, but we will dive deeper into specific changes as they relate to natural processes and hazards. All events that cause a change to Earth’s surface are referred to as “agents of change.” These agents of change include the following:
- Water (hydrologic processes)
- Wind
- Chemical Weathering
- Erosion
- Deposition
- Human Activity
- Tectonic Forces (geologic processes)
- Astronomical Forces (forces beyond Earth)
- Climatic/Atmospheric Forces (processes)
All agents of change work on time scales that are either long term or short term. We will start with an exploration of trends (definition:Changes over time.) by showing how various “agents of change” have affected the planet. Use this ArcGIS StoryMap to visualize each process/hazard/landscape. After reading through the story map, make an attempt to organize the agents of change as short term or long term in the learning object below the map. Agents of change are denoted in brackets or in bold in both the story map and the learning object.
After viewing each location on the storymap, check your understanding by dragging each natural process/hazard/landscape/agent of change to the list of either short term changes or long term changes.
DragandDrop
The map and learning object showed you only a few of the countless changes that have happened in the Earth’s past, recent history, or that are even happening right now. No matter what the change or when it happened, Earth appears as it does today, due to the processes, hazards and human activity that have and continue to shape its landscapes.
The Million Year Journal: If These Rocks Could Talk
Researching Long and Short Term Changes to a Location on Earth
The map above gave you a taste of the various processes that are shaping our planet. Excluding the specific places on that map, choose a location on Planet Earth that you think might have a unique and dynamic past. Consider selecting the study area you have chosen for your culminating activity; you may also select a completely new location of interest.
You must complete the following.
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Research important changes in the geologic, climatic, or hydrologic history of your chosen area. This will include events like major hazards, disasters, glaciations, flooding or any event that contributed to the present day appearance of the landscape.
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Write a list of journal entries from the perspective of the region as if it were a person. Each entry will document these important “life events” that cover the long term or short term changes to this location. Your journal should cover at least five events as individual journal entries.
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Organize each event in chronological order (from past to present). Remember, you will describe each event from the perspective of the landscape experiencing it. Entries should read like a personal journal.
Review this exemplar for the Vancouver, BC Region.
CONSOLIDATION
It’s time to study geography in your own backyard. Earth’s processes are not just happening in other places around the world, they are happening where you live, too!
Local Example
Find a local example of a natural process/agent of change causing change over time. Try to identify the landscape this process creates, and predict how it will alter the existing landscape over time. As you consider the region in which you live, are there:
- Major rivers that will change their course over time or periodically flood?
- Shorelines of lakes or rivers currently being weathered and eroded?
- Effects of a changing climate being felt now or in the future in your community?
- Effects of the most recent glaciation impacting land use or the landscape features?
- Major human activities that are themselves causing a significant change to the landscape?
- Ancient events that played a major role in creating the landscape (asteroid impacts, glacial floods, past volcanism, etc.)?
Your job is to identify ONE natural process/agent of change that operates in your local area and answer the following questions in the discussion.
Questions to Answer:
- Describe the process/agent of change operating in your local area.
- Explain how this process/agent of change has altered the landscape from the past to the present. Or, you may explain how it will alter the landscape from the present to the future?
- Explain whether this process/agent of change works over the long term or the short term.
Keep the following success criteria in mind as you complete this task:
- I can describe the characteristics of patterns and trends using specific terms (e.g., patterns can be dispersed, concentrated, nucleated, linear) (trends can be long term, short term, seasonal, irregular, predictable);
- I can accurately identify patterns and trends in the earth’s natural systems over geologic time;
- I can make connections between planetary and astronomical characteristics to the earth’s physical environment. (e.g., seasons, tide heights, ocean currents, the ozone layer);
- I can make connections between geomorphic agents (e.g., water, ice, wind, chemical processes) and the earth’s physical features (e.g., meanders, valleys, dunes, caves).
Learning Goals and Success Criteria
Learning Skills and Work Habits