In this audio slideshow, an ecologist from the University of Florida describes the radiocarbon dating technique that scientists use to determine the amount of carbon within the permafrost of the Arctic tundra. Understanding the rate of carbon released as permafrost thaws is necessary to understand how this positive feedback mechanism is contributing to climate change that may further increase global surface temperatures.
This video production is a part of a four-panel report from the National Academies' America's Climate Choices project. The video maps out the realm of our accumulated knowledge regarding climate change and charts a path forward, urging that research on climate change enter a new era focused on the needs of decision makers.
This video segment from 'Earth: The Operators' Manual' explores how we know that today's increased levels of CO2 are caused by humans burning fossil fuels and not by some natural process, such as volcanic out-gassing. Climate scientist Richard Alley provides a detailed step-by-step explanation that examines the physics and chemistry of different "flavors" or isotopes of carbon in Earth's atmosphere.
In this video clip from Earth: The Operators' Manual, host Richard Alley discusses China's efforts to develop clean energy technologies and to reduce CO2 in the atmosphere, by building coal plants using CO2 sequestration technology. (scroll down page for video)
Student teams design and build solar water heating devices that mimic those used in residences to capture energy in the form of solar radiation and convert it to thermal energy. In this activity, students gain a better understanding of the three different types of heat transfer, each of which plays a role in the solar water heater design. Once the model devices are constructed, students perform efficiency calculations and compare designs.