This NBC Learn video features climate scientists doing their research on Mt. Kilimanjaro to study the climate of the past. The scientists put the recently observed changes on the glacier into perspective by comparing past climate fluctuations, stressing that the current observed rate of change is unprecedented.

This short video clip summarizes NOAA's annual State of the Climate Report for 2009. It presents a comprehensive summary of Earth's climate in 2009 and establishes the last decade as the warmest on record. Reduced extent of Arctic sea ice, glacier volume, and snow cover reflect the effects of rising global temperature.

This gallery of ten temperature graphs shows global temperatures on different timescales from decades (recently measured temperatures) to centuries (reconstructed) to millions of years (modeled from ice cores).

This video profiles the Arctic Inuit community of Sachs Harbour and its collaboration with scientists studying climate change. Changes in the land, sea, and animals are readily apparent to the residents of Sachs Harbourâmany of whom hunt, trap, and fishâbecause of their long-standing and intimate connection with their ecosystem. Scientists from a climate change study project interview the residents and record their observations. The scientists can use these firsthand accounts along with their own collected data to deepen their understanding of climate change in the polar region.

This video segment describes climate data collection from Greenland ice cores that indicate Earth's climate can change abruptly over a single decade rather than over thousands of years. The narrator describes how Earth has undergone dramatic climate shifts in relatively short spans of time prior to 8000 years ago. The video and accompanying essay provide explanations of the differences between weather and climate and how the climate itself had been unstable in the past, with wide variations in temperature occurring over decadal timescales.

In this video Dr. Richard Alley poses and addresses a simple question: What does carbon dioxide have to do with global warming?

This interactive visualization from the NASA Earth Observatory website compares Arctic sea ice minimum extent from 1984 to that of 2012.

This visualization, from the US Geological Survey, provides a simple schematic of the various pathways that water can take as it cycles through ocean, lakes, atmosphere, surface and ground.

This video segment demonstrates carbon dioxide's role in the greenhouse effect and explains how increasing concentrations of C02 in the atmosphere may be contributing to global warming. Video includes an unusual demonstration of C02's heat-absorbing properties, using infrared film, a researcher's face, and a stream of C02 between them.

This video highlights research conducted at Woods Hole on how heat absorbed by the ocean and changes of ocean chemistry from human activities could lead to a tipping point for marine life and ecosystems. Includes ice bath experiment that models the tipping point of Arctic sea ice.