This classroom resource is a combination of 3 visualizations and accompanying text that illustrate how 3 key natural phenomena - cyclical changes in solar energy output, major volcanic eruptions over the last century, and El Nino/Nina cycles - are insufficient to explain recent global warming.

This is a video overview of the history of climate science, with the goal of debunking the idea that in the 1970s, climate scientists were predicting global cooling.

In this activity, students examine climate variability in the North Atlantic associated with the North Atlantic Oscillation (NOA) in a case study format.

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.

This activity with a lab report instructs students to solve and plot 160,000 years' worth of ice core data from the Vostok ice core using Excel or similar spreadsheets to analyze data. Students learn about ice cores and what they can tell us about past atmospheric conditions and the past atmospheric concentrations of CO2 and CH4.

This activity addresses naturally occurring climate change involving ENSO (El-NiÃo Southern Oscillation). In this activity, students play the role of a policy maker in Peru. First, they determine what sort of ENSO variation is occurring. Then, they must decide how to allocate Peru's resources to manage for possible weather-related problems.

In this activity, students research changes to the environment in the Arctic/Bering Sea over time using oral and photographic histories. Developed for Alaska Native students, this activity can be customized for other regions.

This NOAA visualization video on YouTube shows the seasonal variations in sea surface temperatures and ice cover for the 22 years prior to 2007 based on data collected by NOAA polar-orbiting satellites (POES). El NiÃo and La NiÃa are easily identified, as are the trends in decreasing polar sea ice.

This is a sequence of 5 classroom activities focusing on the El NiÃo climate variability. The activities increase in complexity and student-directedness. The focus of the activities is on accessing and manipulating real data to help students understand El NiÃo as an interaction of Earth systems.

This National Geographic video explains the origins of the El NiÃo Southern Oscillation using animations and shows the impacts on humans, wildlife and habitat, particularly in the United States.