Keeling Curve: Quick Facts

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Line graph showing the Keeling Curve, which tracks atmospheric carbon dioxide (CO2) levels at Mauna Loa from 1965 to 2025. The graph shows a steady upward trend from about 320 to over 420 parts per million, with seasonal fluctuations. An inset highlights the annual cycle of CO2, demonstrating both the short-term oscillations and the long-term increase.

Infographic showing a timeline of major climate change milestones from 1896 to 2025, with key events listed on the left. Insets on the right display a graph of rising atmospheric carbon dioxide levels, diagrams of ocean acidification due to carbon dioxide, and a world map highlighting countries that have signed or ratified the Paris Agreement.

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Global warming Atmosphere Climate change carbon dioxide Troposphere Climatology Paleoclimatology Bioclimatology

Combination shot of Grinnell Glacier taken from the summit of Mount Gould, Glacier National Park, Montana in the years 1938, 1981, 1998 and 2006.

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Archaea at Midway Geyser Basin in the Grand Prismatic Spring, Yellowstone National Park, Wyoming. Largest hot spring in Yellowstone, third largest in the world. Temp. 147-188F Dim. 250x380 ft. Archaeon, archeon, Yellowstone Geysers, algae

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