This is the first of nine lessons in the Visualizing and Understanding the Science of Climate Change website. This lesson is an introduction to Earth's climate and covers key principles regarding Earth's unique climate, atmosphere, and regional and temporal climate differences.

In this activity, students examine images of alpine glaciers to develop an understanding of how glaciers respond to climate change. They record, discuss, and interpret their observations. They consider explanations for changes in the size and position of glaciers from around the world. They develop an understanding that the melting (retreat) of glaciers is occurring simultaneously on different continents around the world, and, thus, they represent evidence of global climate change.

The activity takes a hands-on approach to understanding El NiÃo by physically showing and feeling the process. It consists of an El NiÃo demo to be performed by the teacher and observed by the class as well as an experiment to be conducted by the students themselves individually or in pairs to illustrate the connection between water temperature and atmospheric temperature. Students are asked to make conclusions based on their findings and then examine the chain of events stemming from El NiÃo.

This is a lab about evidence for past climate change as captured in ice sheets of Greenland and Antarctica. Students investigate climate changes going back thousands of years by graphing and analyzing ice core data from both Greenland and Antarctica. They use information about natural and human-caused changes in the atmosphere to formulate predictions about Earth's climate.

In this activity, students examine pictures of pollen grains representing several species that show the structural differences that scientists use for identification. Students analyze model soil samples with material mixed in to represent pollen grains. They then determine the type and amount of 'pollen' in the samples and, using information provided to them, determine the type of vegetation and age of their samples. Finally, they make some conclusions about the likely climate at the time the pollen was shed.

This activity relates water temperature to fishery health within inland freshwater watersheds as a way to explore how environmental factors of an ecosystem affect the organisms that use those ecosystems as important habitat.

In this learning activity, students use a web-based geologic timeline to examine temperature, CO2 concentration, and ice cover data to investigate how climate has changed during the last 715 million years.

In this activity, students use authentic Arctic climate data to unravel some causes and effects related to the seasonal melting of the snowpack and to further understand albedo.

In this activity, students reconstruct past climates using lake varves as a proxy to interpret long-term climate patterns and to understand annual sediment deposition and how it relates to weather and climate patterns.

In this jigsaw activity, students explore meteorological data collected from Eureka, Canada to try to decide when would be the best time for an Arctic visit.