Rapid warming and other large-scale climate changes threaten human and ecological systems.
Teaching this principle is supported by thirteen fundamental concepts:
A. As of 2021, Earth had warmed by about 1.1°C (2°F) above preindustrial levels. Most of this warming has occurred since 1980. The current rate of warming is roughly 30 times faster than the rate at which Earth warmed as it emerged from the last ice age.
B. The last time the amount of carbon dioxide in the atmosphere was as high as it is today was about 3.2 million years ago, when the world was significantly warmer and sea levels were between 18 and 63 feet (5.5 to 19 meters) higher than today. Learn more about past climate
C. Human societies developed over the past 10,000 years during a very stable period in Earth's climate history. The rapid rise in temperatures and resulting climate changes since 1980 mean that the economic, transportation, agricultural, and social systems we rely on are vulnerable. Learn more about climate change impacts on social systems
D. Climate change is already increasing the severity, geographic scale, and frequency of extreme events, such as heatwaves, floods, strong storms, droughts, and wildfires around the United States and the world. As the world warms, these events will become even more extreme, worsening existing social inequalities and leading to greater health, resource, and migration challenges. Existing societal challenges, intensified by increasing climate change, will exacerbate the drivers of instability and threaten both national and global security. To deal with the direct effects of extreme events, as well as the increased instability resulting from them, the need for humanitarian assistance will increase worldwide. Learn more about changes to extreme events
E. Globally, a warmer atmosphere holds more total water vapor, and some areas will get wetter. Warmer air with more water vapor also causes heavier rainfall during storms, which can lead to flooding. However, over many regions, temperature changes will outpace the effects of increases in humidity, making dry places even drier and droughts more intense.
F. Changing precipitation and snowmelt patterns are altering the distribution of Earth's freshwater and the timing of runoff. Droughts are becoming more frequent and severe in many regions, while, at the same time, extreme precipitation events are becoming more frequent and intense in other regions. Some regions are experiencing both—more frequent or severe droughts in the summer, and more extreme precipitation events in the winter. These and other climate change impacts threaten the quality and reliability of water supplies. Learn more about the changing water cycle
G. Global warming is causing the global average sea level to rise. As ocean water warms, it expands, taking up more space. Water from melting land ice is also being added to the ocean, raising sea levels. As the sea level rises, salt water contaminates coastal freshwater sources, damages coastal homes and infrastructure, harms coastal ecosystems, and inundates islands and low-lying land. Sea level rise also increases the risk of damage to buildings and infrastructure from high tide flooding and storm surge. Learn more about the impacts of climate change on coastal communities
H. The ocean has slowed climate change by absorbing huge amounts of heat and carbon. About 90% of the warming caused by greenhouse gas emissions has been absorbed by the ocean, altering its global circulation patterns and threatening marine life. The ocean has also taken up 25% of all carbon dioxide produced by human activities, making it more acidic and leading to harmful impacts on marine species, food webs, and coastal economies. As climate change continues, the ocean's capacity to store heat and carbon is likely to weaken, reducing its ability to buffer the effects of greenhouse gas emissions. Learn more about the ocean and climate change
I. All species, including humans, survive within specific ranges of temperature, precipitation, humidity, sunlight, and other climate conditions. Organisms exposed to climate conditions outside their normal ranges must adapt or move elsewhere, or they may face negative health impacts. If climate conditions sufficiently alter a species' habitat, consequences can include extinction. Changes to the abundance of different species can threaten the stability and survival of their ecosystems. Learn more about ecosystem changes
J. As local climate conditions change, many organisms, including animals, plants, and microbes, are attempting to move to areas with more favorable conditions. However, their movement can be limited or prevented by natural barriers such as mountains, human-built infrastructure such as roads, or competition with other species. The timings of blooms, migrations, and hibernations have changed and will continue to change, sometimes dramatically, potentially altering food webs and spreading infectious diseases. These processes disrupt existing ecosystems and can threaten the survival of entire species, biomes, and human livelihoods. Learn more about ecosystem impacts
K. The impacts of climate change and other stressors may drive people to leave their homes temporarily or permanently, either within the same country or across a border. For example, rising temperatures and shifting rainfall could lead to increased crop failures, compelling farmers to seek more reliable livelihoods in nearby cities or neighboring regions. Climate migration is one type of human migration, which can have many complex causes and impacts. If migration is sudden and unplanned, it may increase demand for scarce resources and potentially exacerbate tension between migrants and local communities. Governments may also struggle to provide adequate services amid large-scale displacement. Learn more about climate change and migration
L. Climate change negatively impacts human health through more frequent and severe extreme heat and other extreme events; increased transmission of infectious and vector-borne diseases; declines in food and water security; and degraded air and water quality. Exposure to extreme events can result in feelings of vulnerability, uncertainty, and anxiety or depression, with negative impacts on mental health. Marginalized and low-income populations tend to be more exposed to climate hazards and associated health impacts than other groups. Learn more about climate change and human health
M. Climate change can harm businesses, governments, and economies through costly disruptions to services and supply chains, damage to infrastructure, and lost productivity. At the same time, climate solutions will create new economic opportunities for organizations. Learn more about climate change and the economy
Bringing these ideas into your classroom
Here are a few pedagogic strategies for teaching about climate impacts.
- Because climate change affects so many systems, the theme can be woven into a range of topics throughout a course or a unit. Subjects such as history, economics, or health can all touch on climate change. Climate impacts needn't only be addressed within the specific context of an earth science class.
- Student teams can investigate climate impacts on different parts of the earth system. Teams could learn how climate is affecting the cryosphere, coral reefs, birds, forests, native peoples, agriculture, transportation, diseases, national security, and many other avenues.
- A geographic approach could be used to examine impacts in different parts of the world.
- Students could write or read narrative stories about how climate affects people.
- Students could use imaginary time travel to visit the climate of the future, which would vary depending on the actions we take today.
- Students could use local climate data such as temperature, snowfall, and streamflow. Similarly, students could learn about economic impacts such as maple syrup production, crop yields, and winter recreation.
- Role-playing activities could be used to explore how the climate affects people in different walks of life such as farmers, construction workers, insurance agents, or pilots.
Teaching materials from the CLEAN collection
These concepts are well-represented in the CLEAN resources. One way to narrow the search is to look for a specific type of impact like melting ice and permafrost, sea-level rise, extreme weather, or impacts on plants and animals. Alternatively, you can search by region, like the US Southwest or US coastal areas.
Middle school
- Drought: Identifying Impacts and Evaluating Solutions - In this set of activities, students learn about impacts of drought through news videos of communities facing serious water shortages, analyze drought data and models, and research and evaluate potential solutions. This lesson works well as a component within a larger unit on climate change, its impacts, and ways to address the resulting issues.
- After the Ice - Part 2: Our Land - This 7-minute video illustrates how the historic homeland for Arctic Native Americans is being affected by climate change. Shorefast ice and pack ice are present for a shorter part of the year. This has profound affects on the way of life in the Bering Sea region, to the point where the community may have to relocate.
- Carbonated Communities - This series of two lessons uses cutting-edge scientific research on the effects of climate change on communities in the intertidal. Through a combination of a dynamic presentation and several videos, students are introduced to the effects of climate change on the ocean (ocean acidification and temperature increase) and what is known about how ocean organisms are affected. Then students read and interpret graphs and construct a scientific explanation based on data from this research.
- Earth Artistically Balanced - In this activity, students learn about the complexities of Earth's climate system and the different factors contributing to Earth's energy balance. Next, students categorize the factors that influence climate as warming or cooling factors. To conclude, students design art pieces to depict the science behind Earth's climate system and share these artistic creations with families and communities.
High school
- HEART Force Drought Game - In this interactive game, students solve challenges that their community faces during the course of an extreme drought event by using available individual and community resources. Students work in three resilience teams to determine the strategies that they will invest in as a community as the drought situation evolves.
- Living Landscapes: Assessing Climate Change Impacts on Fish - Interactive map tool to assess how rising stream temperatures could affect native fish of the Northwest. Lesson concepts include the relationship between water temperatures, dissolved oxygen levels in streams, and the impacts of changing temperatures on native fish. Focused skills include use of an interactive map to assess how stream temperatures are expected to change and the impact on native fish.
- Advanced high school students can do an in-depth analysis of coral reef health: Using Data to Identify Hot Spots and Predict Bleaching Events.
- Liz Hadly Tracks Impact of Climate Change in Yellowstone is a video that illustrates impacts to Yellowstone National Park's ecosystems. Examples include pine bark beetles and drought.
- Resource Watch - Resource Watch features hundreds of data sets all in one place on the state of the planet's resources and citizens. Users can visualize challenges facing people and the planet, from climate change to poverty, water risk to state instability, air pollution to human migration.