The role of simple models in understanding the low CO2 emissions regime and the ZEC

Simple models have been used in a variety of ways to summarize Earth system processes related to global warming and its mitigation. This poster will provide a pedagogical survey of the many uses to which these models have been put, focusing especially their role in understanding the regime of prolonged low carbon dioxide (CO2) emissions following emissions peak and decline.  We will show that the low emissions regime is exactly where path independence between global warming and cumulative CO2 emission breaks down, giving rise to the possibility of a substantial zero emissions commitment (ZEC). Using a few different simple models, the factors affecting the ZEC in low emissions scenarios and its relation to path dependence will be described, and we will furthermore examine the observability of respective model parameters affecting the magnitude of ZEC.