In studying Earth’s carbon cycle—the exchange of carbon between the planet’s land, atmosphere, and oceans—scientists are trying to understand the role played by huge tropical rainforests such as the Amazon River basin. In particular, they want to determine how long an ecosystem stores atmospheric carbon dioxide in its plants, soils, and rivers. Karis McFarlane is an environmental scientist who has been using radiocarbons to study and better understand this cycle since 1999. She will discuss the ways radiocarbon is used to study carbon cycling in ecosystems and why it's unique and important for climate change. She will focus on the importance of understanding how much and for how long carbon is sequestered in soil and the role it plays in the carbon cycle. This session is a must for all environmental science educators.