METHANE BIFOCAL MODELING

Bifocal modeling is an instructional and analytical approach that connects two complementary "views" of the same phenomenon: (1) directly measurable macroscopic behavior, and (2) a simplified mechanistic model that explains why that behavior occurs. In the methane greenhouse effect experiment, bifocal modeling links real-time environmental data from a small enclosed space with a conceptual model of infrared absorption and heat trapping by CH₄. This conceptual model refers to molecular vibration of CH₄ that consist of asymetric stretching and bending which active interaction with IR but symteric stretching and doubly degenerate bending are not active with IR In this setup, an Arduino microcontroller serves as the data acquisition unit. Methane concentration is monitored using an MQ-4 gas sensor, while temperature is measured using a DHT22 sensor. The space is exposed to a controlled heat source (a lamp), and the Arduino continuously records the sensor readings at fixed intervals. The macroscopic "focus" view is represented by data showing methane levels (in ppm) along with temperature increases and approaches to steady state. This view allows the user to identify patterns such as faster warming rates, higher peak temperatures, or slower cooling as methane levels increase.