This video is part two of a seven-part National Academies series, Climate Change: Lines of Evidence. The video outlines, with the use of recent research and historical data, how we know that the Earth is warming.

This video describes the impact of extreme heat on Philadelphia in the summer of 2011 and how the city is adapting to new expectations about its weather. It uses this example to introduce the new national climate normals, released by NOAA's National Climatic Data Center (NCDC) that summer.

In this video scientists discuss possible rates of sea level rise, storms and resulting damage, rising temperatures and melting ice, and their collective effects on ecosystems.

This video features a number of different climate scientists describing the effects of the increasing amount of carbon dioxide on global climate and proposing a series of solutions to mitigate these effects. Video addresses health problems and other costs to humans associated with climate change.

This video reviews how increasing temperatures in the Arctic are affecting the path of the jet stream, the severity of storms, and the length of individual weather events (rain, storms, drought).

In this activity, students learn about the urban heat island effect by investigating which areas of their schoolyard have higher temperatures - trees, grass, asphalt, and other materials. Based on their results, they hypothesize how concentrations of surfaces that absorb heat might affect the temperature in cities - the urban heat island effect. Then they analyze data about the history of Los Angeles heat waves and look for patterns in the Los Angeles climate data and explore patterns.