This is the seventh of nine lessons in the 'Visualizing and Understanding the Science of Climate Change' website. This lesson addresses climate feedback loops and how these loops help drive and regulate Earth's unique climate system.

In this activity, students will use oxygen isotope values of two species of modern coral to reconstruct ambient water temperature over a four-year period. They use Microsoft Excel, or similar application, to create a spreadsheet of temperature values calculated from the isotope values of the corals by means of an algebraic equation. Students then use correlation and regression techniques to determine whether isotope records can be considered to be good proxies for records of past temperatures.

Interactive visualization that provides a basic overview of the Earth's carbon reservoirs and amount of carbon stored in each, CO2 transport among atmosphere, hydrosphere, geosphere, and biosphere, and a graph comparing global temp (deg C) and atmospheric CO2 levels (ppm) over the past 1000 years.

This video segment demonstrates carbon dioxide's role in the greenhouse effect and explains how increasing concentrations of C02 in the atmosphere may be contributing to global warming. Video includes an unusual demonstration of C02's heat-absorbing properties, using infrared film, a researcher's face, and a stream of C02 between them.

This is an interactive visualization of the Carbon Cycle, through short-term and long-term processes.

This interactive animation focuses on the carbon cycle and includes embedded videos and captioned images to provide greater clarification and detail of the cycle than would be available by a single static visual alone.

This is an activity designed to allow students who have been exposed to the El NiÃo-Southern Oscillation to analyze the La NiÃa mechanism and predict its outcomes in a case study format.

This video describes the foundation Plant for the Planet, a foundation created by a 9-year-old German boy, Felix. This foundation has planted more than 500,000 trees in Germany, which he says help sequester carbon and reduce greenhouse gas emissions. The student rallies, first his community and then other children, to plant millions of trees to offset our energy-use emissions.

This short video describes the Hestia project - a software tool and data model that provide visualizations of localized CO2 emissions from residential, commercial, and vehicle levels, as well as day versus night comparisons, in the city of Indianapolis.

In this visualization, students can explore North American fossil fuel CO2 emissions at very fine resolutions of both space and time. The data is provided by the Vulcan emissions data project, a NASA/DOE funded effort under the North American Carbon Program.