During an October 2010 webinar, scientist Larry Mayer talked about carbon - how it moves between air, sea and sediment in earth systems. The topic has important implications for climate change and he described carbon as a "genie in a bottle" that humans are now releasing. His series of three concept maps explained current best estimates about "standing stock" of carbon in different locations and forms, and illustrated rates of transfer between, and the residence times in, each location.