This table is a reference tool for rapidly locating Wikipedia articles on Historic and Prehistoric climate indicators of all types.
Method | Type | Basis | Interpret | Instruments | Back To | |
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Varve Analysis | Geological | Annual bands of seasonally differing particle size in glacial lake deposits | Samples carry Proxies. Thicker bands = warmer, wetter weather | Visual and Microscope | ca 13,000 yrs BP | |
Dendroclimatology | Biological | Annual bands of seasonally differing woody growth tissue in trees | Thicker bands = warmer and/or wetter weather, although some studies found thinner trunks for higher temperatures [1] | "The median values for height, stem diameter and all biomass measurements at elevated growth temperatures were always near 1 for evergreens, indicating that for every study that found increased growth with warming, there were a similar number that found a decrease " | Visual and Microscope | ca 10,000 yrs BP |
Ice cores | Geological | Annual (or periodic) layers of differing ice crystals in glaciers and ice caps | Samples carry Proxies. Thicker bands = snowier weather | Chemical and Mass Spectrometer | ca 800,000 yrs BP | |
Speleothems | Geological | Layers of seasonally differing stalagmite/stalactite deposits in limestone caves | Samples carry Proxies. Thicker bands = warmer, wetter surface weather | Visual and Microscope | ca 500,000 yrs BP | |
Sun Spots | Astronomical | Number of spots visible on the surface of the Sun over various periods | More spots = warmer weather cycles (this is controversial) | Visual and Telescope | 1700 AD | |
Oxygen Isotope Analysis, see marine isotope stage | Geochemical Climate Proxy | Ratio of Oxygen-18 to Oxygen-16 in calcite from deep sea sediment, and coral cores | More Oxygen-18 = colder climatic periods | Mass Spectrometer | ca 542,000,000 yrs BP | |
Beryllium-10 Analysis | Geochemical Climate Proxy | Ratio of Beryllium-10 to daughter isotopes in dust from ice cores | Produced in atmosphere by cosmic rays and absorbed into the hydrologic cycle. Level of Beryllium-10 has been shown to closely match recent solar activity measured by sun spots | Mass Spectrometer | ca 80,000 yrs BP |
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