Tree-Ring Formation, Isotopes, and El Nino in Ponderosa Pine of the Southwest

美国亚利桑那州大学史蒂文·W·莱维特ATM-9810474标题：美国西南部黄皮松的年轮形成、同位素和厄尔尼诺现象过去几个世纪以来，美国西南部的气候条件和变化是通过标准的树状气候学研究来进行的。对重建数据和现代仪器数据的分析表明，该地区的气候似乎特别受到厄尔尼诺遥相关和每年西南夏季风的反复无常的影响。最近，稳定同位素形式的新工具已成为通过分析树木年轮和降水来探测现在和过去气候的可行选择。该奖项支持一项旨在确定树木年轮同位素组成与环境(包括气候)之间联系的研究。拟议研究的主要重点将是通过增加同位素子程序来推进树木年轮生长过程的数值模型。过程模型开发的基本目标是获取气候和大气和土壤(水)的同位素组成的输入，并准确地生成年轮内单个木材细胞的同位素变化(和细胞大小)的详细模式。同位素实验和模型开发将齐头并进，以更好地了解同位素组成与气候的关系。随着树木年轮同位素在气候研究中的使用不断增加，特别是在亚年一级，这一模型应能为理解同位素结果提供重要的指导。

Abstract ATM-9810474 Leavitt, Steven W. University of Arizona Title: Tree-Ring Formation, Isotopes, and El Nino in Ponderosa Pine of the Southwest Climate conditions and variability over several centuries in the American Southwest have been investigated via standard dendroclimatological research during the past few decades. Analysis of reconstructed data and modern instrumental data indicates this region's climate appears particularly impacted by El Nino teleconnections and the vagaries of the annual southwestern summer monsoon. New tools in the form of stable isotopes have recently become a viable option for probing present and past climate by means of analysis of tree rings and precipitation. This award supports a study designed to establish the linkage between tree-ring isotopic composition and environment (including climate). The primary focus of the proposed research will be to advance the numerical tree-ring growth process model through the addition of isotopic subroutines. The fundamental goal of the process model development is to take inputs of climate and isotopic composition of atmosphere and soil (water), and accurately generate the detailed patterns of isotopic variation (and cell size) for individual wood cells within rings. The isotopic experimentation and model development will go hand-in-hand to better understand relationships of isotopic composition and climate. With escalating use of tree-ring isotopes in climate research, especially at the subannual level, this model should provide important guidance to understanding the isotopic results.