Climatic Data, Tree Ring Records

PAST CLIMATES CAN be reconstructed by the use of the relationship between the climate and tree-growth parameters (dendroclimatology). Dendroclimatology is a sub-discipline of dendrochronology, which is the analysis of tree rings, including the dating of annual rings and study of patterns of ring characteristics, such as width, density, and isotopie composition. Annual growth rings of trees are natural recorders of climatic conditions (a proxy variable).

Outside the tropics, in the temperate and boreal zones with a distinct growing season and a strong seasonality in either temperature or rainfall, diameter growth of trees is distinguished by the formation of tree rings. Each growing season, new cells are produced by the vascular cambium (a cell layer that separates bark from wood).

While those cells formed toward the outside of ...