Exploring climate change: A graphical journey through time

Commonly, efforts to raise students' awareness of global warming often involve impactful videos or images that focus on consequences rather than causes. However, these resources, while realistic, can feel distant from students' daily lives, falling short of instigating the environmental consciousness educators seek. To address this challenge, we propose an alternative approach—utilizing graphs of real data records and their interpretation. This method could be even more impactful than images and allows us to work on various mathematical skills, such as graph description, pattern identification, and trend analysis.

This poster introduces an activity designed to be carried out over two or three sessions of one hour, and utilizing two famous graphs: The Keeling Curve and the Vostok ice core record. The prerequisite concepts needed to carry out the activity are the energy balance and the greenhouse effect. Initially, we must erase the CO₂ values from the Y-axis of both graphs.

The Keeling Curve serves as the foundation for introducing concepts such as instrumental data and variation patterns, allowing us to observe the continuous increase in CO₂ concentration throughout the entire record. The teacher assumes the role of a skeptic, posing the question: "Can we unequivocally attribute this increase to human activity?" This query prompts students to consider the data needed for certainty, leading them to the realization that preindustrial CO₂ concentration data are crucial to answering the question.

Following this, we present the paleoclimatic record of atmospheric CO2 extracted from the Vostok ice core in Antarctica, covering the past 800,000 years. However, we omit the current outlier data (since 1950 to present), leaving it for participants to complete at the conclusion of the activity. During the session, students are guided to understand core concepts through graph interpretation. Upon observing the glacial-interglacial pattern, students are tasked with predicting CO₂ fluctuations for the next 100,000 years by extending the graph. After that, they receive the erased CO₂ Y-axis values from the graph and are tasked with finding the corresponding CO₂ concentration for that specific day to add to the chart. This value entirely disrupts the predicted pattern, and the resulting graph often prompts cognitive dissonance, leaving a lasting impact on students.

This activity enhances scientific understanding of climate change and also emphasizes the seriousness of the current environmental emergency.