Dendrochronological reconstruction of long-term precipitation patterns in Basaseachi National Park, Chihuahua, Mexico

The purpose of this study was to reconstruct the precipitation at Basaseachi National Park (BNP) in Chihuahua, Mexico.Tree-ring samples from pine species including Pinus durangensis, P. lumholtzii and P.engelmannii were collected in and near BNP and they were cross-dated with existing chronologies. Ring widths of each sample were measured and models to remove non-climatic trends from the data were applied. The relationship between precipitation from the weather station in Yécora, Sonora, and the ring width indices were modeled using a bivariate linear regression (r² = 0,59, p<0.01). It was found that precipitation from the months of October, December, February and April was most highly correlated with tree ring growth. The reconstruction extends 225 years from 2007-1782. During this time period there were thirteen severe droughts, ten of which affected large areas in northern and central Mexico.