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.

This video, from the US Department of Energy, shows the basics of how a PV panel converts light radiated from the sun into usable power, whether on the electric grid or off, and without emissions or the use of fossil fuels.

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.

This video highlights a team of scientists who work on reconstructing the mass extinction that occurred 250 million years ago, the end of the Permian Period, and wiped out the majority of life on our planet, resetting the evolution of life. Clues suggest that deadly bacteria might have set off a chemical chain reaction that poisoned the Permian seas and atmosphere.

In this activity, students consider the impact and sustainability of use of different classes of biofuels on the economy, the environment, and society. Students also learn about bioelectricity and how converting biomass to electricity may be the more efficient way to fuel cars in the 21st century.

This activity from the Department of Energy provides background information about solar ovens and instructions on building a simple model solar cooker.

This video from a 2005 NOVA program features scientists who study how the Jakobshavn Isbrae glacier in western Greenland is shrinking and moving faster due to increased melting over the past ten years. The video includes footage of scientists in the field explaining methods and animation of ice sheet dynamics leading to faster glacier movement.

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.

This collection of photos from the NASA Climate website features images related to global change. Not all images show change caused directly by climate change and energy use, and descriptive captions indicate causes for change in most of the images.

This video addresses acidification of the ocean and the ecological and economic implications of the resulting pH change on marine life. It includes information about how ocean acidification resulting from increased absorption of CO2 from the atmosphere is affecting ocean species such as sea urchins and oysters. Scientists from the University of California at Santa Barbara discuss their experiments with sea creatures in acidic sea water. There is an associated lesson plan and classroom activity that has students test the effects of CO2 on water pH.