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.

In this activity from NOAA's Okeanos Explorer Education Materials Collection, learners investigate how methane hydrates might have been involved with the Cambrian explosion.

Data-centric activity where students explore the connections between an observable change in the cryosphere and its potential impact in the hydrosphere and atmosphere. Students analyze the melt extents on the Greenland ice sheet from 1992-2003. Students also learn about how scientists collect the data.

This short video from Climate Central explains the technology used to monitor changes in Arctic sea ice. Long-term tracking (since the late 1970's) shows Arctic sea ice has been on a steady decline and this could have significant implications for global temperatures.

This video montage of spectacular NASA satellite images set to music shows different types of ice and ice features as well as descriptions of satellite-based measurements of ice cover. Text captioning provides guidance as to issues related to changing global ice cover and its measurement.

This is a real-time map of current drought conditions in the US, which can be zoomed to the state level, with access to many more resources at that level. Some of these include the National Drought Regional Summaries and animations of historical data.

This series of visualizations show the annual Arctic sea ice minimum from 1979 to 2010. The decrease in Arctic sea ice over time is shown in an animation and a graph plotted simultaneously, but can be parsed so that the change in sea ice area can be shown without the graph.

In this activity, students read an article condensed from several NASA articles about the impact of deforestation on the atmosphere and answer review questions. They then use Google Earth and current NEO data to examine relationships between forest fires and atmospheric aerosols.

In this activity, students create graphs of real temperature data to analyze climate trends by analyzing the global temperature record from 1867 to the present. Long-term trends and shorter-term fluctuations are both evaluated. The data is examined for evidence of the impact of natural and anthropogenic climate forcing mechanisms on the global surface temperature variability. Students are prompted to determine the difficulties scientists face in using this data to make climate predictions.

This is a graphic that illustrates anomalies in tropospheric temperatures over a 50-year time period and is based on 7 different datasets superimposed on each other. It is one of 9 climate indicators documented in the AMS State of the Climate report.