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.

These animations depict the three major Milankovitch Cycles that impact global climate, visually demonstrating the definitions of eccentricity, obliquity, and precession, and their ranges of variation and timing on Earth.

An interactive simulation of Earth's seasonal dynamics that includes the axial tilt and other aspects of Earth's annual cycle.

This is part of a larger lab from the University of Nebraska at Lincoln: http://astro.unl.edu/naap/motion1/motion1.html

Hands-on laboratory activity that allows students to investigate the effects of distance and angle on the input of solar radiation at Earth's surface, the role played by albedo, the heat capacity of land and water, and how these cause the seasons. Students predict radiative heating based on simple geometry and experiment to test their hypotheses.

An applet about the Milankovitch cycle that relates temperature over the last 400,000 years to changes in the eccentricity, precession, and orbital tilt of Earth's orbit.

This animated visualization of precession, eccentricity, and obliquity is simple and straightforward, provides text explanations, and is a good starting place for those new to Milankovitch cycles.

In this activity for undergraduates, students explore the CLIMAP (Climate: Long-Range Investigation, Mapping and Prediction) model results for differences between the modern and the Last Glacial Maximum (LGM) and discover the how climate and vegetation may have changed in different regions of the Earth based on scientific data.

This Motions of the Sun Lab is an interactive applet from the University of Nebraska-Lincoln Astronomy Applet project.

This short video, adapted from NOVA, explains how Earth's position relative to the Sun might be responsible for the dramatic shift in the climate of what is now the Saharan nation of Djibouti.