Safety and evidence boundary
Use public system diagrams and aggregate environmental data. Field observations must remain non-contact and safe. Do not enter hazardous water, drains, industrial sites, disaster areas, or collect protected materials. Distinguish measured fluxes from arrows drawn in a model.
Explicit science instruction
Photosynthesis moves inorganic carbon into organic molecules; respiration and decomposition return carbon to inorganic forms. Oceans exchange carbon with the atmosphere and store dissolved inorganic/organic carbon. Sedimentation, weathering, volcanism and fossil-carbon processes operate over longer timescales.
Human combustion and land-use change alter fluxes faster than some reservoirs can equilibrate.
Worked example with reasoning
A fictional forest takes up 120 units/year by photosynthesis, returns 70 by plant respiration and 35 by decomposition. Net biological storage in the simplified accounting is 15 units/year before disturbances or export are considered.
Guided question
Why is “trees absorb carbon” an incomplete carbon-budget statement?
Independent work
- Build a six-reservoir carbon model.
- Calculate a simplified net flux.
- Add combustion and ocean exchange.
- State which arrows are measurements versus modeled estimates.
Misconception check
Carbon is not destroyed when organisms respire; carbon atoms change molecular form and reservoir.
Formative understanding check
Photosynthesis 100, respiration+decomposition 85. Simplified net storage?
Worked response
15 units per stated time, before other fluxes.
Open-book formative practice only; not an official mastery attempt or grade.
Mentor evidence conference
Ask Archaemenes to challenge your systems model, quantitative interpretation, alternative explanations, and boundary conditions.
Open ArchaemenesTeacher guidance
Foundation: use pre-labeled reservoirs. Core: balance a simplified carbon budget. Extended: compare short-term biological and long-term geological carbon fluxes.
Preserve learning evidence
Keep models, calculations, graphs, corrections and uncertainty notes in the matching Week 32 evidence field.