Proxy Methods

Proxy measures are measurements of physical, chemical, or biological processes that depend on the weather, and therefore provide an indication of past climates.

Researcher works with a drill that extracts ice cores from glaciers during the 2003 Antarctic Megadunes expedition.

Ted Scambos & Rob Bauer, NSIDC

Boreholes

Corals

Glacial Extent

Ice Cores

Isotopes

Paleomagnetism

Tree Rings

  • The Past Million Years Featured Article The Past Million Years The Past Million Years

    Climate researchers have reliable temperature records from weather stations dating back to about 1850. To study variations in climate that pre-date the advent of weather... More »

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