Question

part 1c: describe a feedback loop involving permafrost thaw that includes at least two earth systems (spheres) from the list below.
your response may include multiple feedback loops, if that helps you talk about two systems more easily.
you can use ideas we have built as a class throughout the unit as part of your thinking.
you may annotate on the model to support your response.
atmosphere biosphere cryosphere geosphere hydrosphere
one feedback loop is between the cryosphere(permafrost) and the atmosphere. as permafrost thaws, it releases greenhouse gases (methane and carbon dioxide) into the atmosphere. these gases cause more warming, which in turn leads to more permafrost thaw. another possible aspect is the impact on the biosphere. thawed permafrost can change habitats, affecting plant and animal life.
some scientists have argued that permafrost thaw could be even more damaging than the model above predicts. this is because thawing permafrost can allow chemical reactions that combine carbon in the soil (c) with oxygen in the air (o₂) to make carbon dioxide (co₂).
part 2a: what questions would you need to ask about the scientists idea to find out if it would change the feedback loops in the first permafrost thaw model?

Explanation:

To determine if the scientists' idea changes the feedback - loops, questions could include: What is the rate of the chemical reaction combining soil carbon and air oxygen? How much additional carbon dioxide will be produced compared to the initial model? What impact will this additional carbon - dioxide have on the atmosphere - cryosphere feedback loop? Will it affect the biosphere in different ways than the original model?

Answer:

• What is the rate of the chemical reaction between soil carbon and air oxygen?
• How much extra carbon dioxide will be generated compared to the initial model?
• How will the additional carbon dioxide impact the atmosphere - cryosphere feedback loop?
• Will it have different effects on the biosphere than the original model?