Carbon is constantly on the move through the different components of Earth’s Geosphere and Biosphere, but at very different timescales and spatial scales. For example, the processes that move carbon from the ocean (hydrosphere) to the lithosphere happen over a very large spatial scale and can take timescales of millions of years. In contrast, the process that moves carbon from the leaves of plants in the biosphere to the atmosphere happens in minutes and at a spatial scale as small a leaf’s surface. In this Lab, you will have the opportunity to explore how the global carbon cycle and subsets of the carbon cycle operate on very different spatial scales and timescales. In Part A, you will explore the role of food webs in a subset of the natural carbon cycle by taking on the role of a carbon atom moving through a Lodgepole Pine forest carbon cycle. You will learn that photosynthesis, respiration, ingestion, and decomposition are key food web processes that move carbon from one forest reservoir to another. In Part B, you will investigate how carbon moves throughout the global carbon cycle. In Part C, you will apply system-thinking strategies to learn about the interconnectedness of the Earth system, feedback loops, and how changes in one part of the carbon cycle system can lead to other changes in the carbon cycle system. After completing this Lab, you should be able to: • Describe how the primary carbon cycle processes of photosynthesis, respiration, decomposition, ingestion and combustion transport and transform carbon compounds as they move throughout Earth’s Geosphere and Biosphere. • Identify the four major carbon reservoirs and explain how carbon can move from one reservoir to another. • Provide examples of the various time scales at which carbon moves through Earth’s Geosphere and Biosphere. • Describe the effects of negative and positive feedbacks on the carbon cycle system.