Tree thermometers and commodities: Historic climate indicators

In four modern trees, hydrogen and oxygen isotope ratios track the modern temperature records.In a 2000-yr sequence of a Japanese cedar, there are the same periodicities of variation of D/H and O¹⁸/O¹⁶ as have been found in O¹⁸/O¹⁶ in a Greenland ice well.The same periodicities are found in uranium and organic carbon concentrations versus depth in a sea core from the Santa Barbara Channel, and in carbon-14 variations in a sequence of Bristlecone pine from southern California.In a 2000-yr sequence of Japanese cedar and in a 1000-yr sequence of European oak D/H and O¹⁸/O¹⁶ are related to each other by a slope of 8, just as they are in world-wide precipitation.In a 72-yr sequence of Sequoia gigantea, measured year by year for its oxygen isotope ratios, the 10.5-yr cycle of sunspot numbers found, but not the 21-yr cycle of sunspot magnetism; this we believe indicates that the sun is affecting the earth's climate with non-magnetic particles, probably photons.All these phenomena are related to periodic changes in sea surface temperature caused by periodic changes in the sun.