Climate Change Detection and Attribution using observed and simulated Tree-Ring Width
Climate Change Detection and Attribution using observed and simulated Tree-Ring Width
复制标题
DOI：
10.5194/cp-2021-80
复制
发表时间：
2021-07
影响因子：
4.3
通讯作者：
J. Franke;M. Evans;A. Schurer;G. Hegerl
中科院分区：
文献类型：
--
作者：
J. Franke;M. Evans;A. Schurer;G. Hegerl
抽象。古气候变化对外部辐射强迫的探测和归因依赖于模拟数据的统计重建回归。然而，这一过程可能会受到潜在的古气候观测的平稳性和单变量线性响应的假设。在这里，我们通过回归树轮宽度（TRW）的观测TRW模拟，这是从气候模拟的前向建模的D&A研究。温度和湿度敏感TRW模拟显示不同的模式在时间和空间。温度敏感的TRW观测和模拟显着相关的北方半球的平均值，其变化是由于最密切的火山强迫模拟。在十年平滑的时间指纹，我们发现观察到的响应显着更大和/或更持久的模拟响应。模拟TRW的水分有限的树木的模式是一致的观察到的异常在两年后的主要火山爆发。我们可以第一次将水分限制的树木年轮记录中的时空指纹归因于火山强迫。这些结果表明，使用非线性和多变量代理系统模型在古气候检测和归因研究可能允许更现实的，空间分辨和多变量指纹检测研究，和评估气候对外部辐射强迫的敏感性，比以前可能的。
Abstract. The detection and attribution (D&A) of paleoclimatic change to external radiative forcing relies on regression of statistical reconstructions on simulations. However, this procedure may be biased by assumptions of stationarity and univariate linear response of the underlying paleoclimatic observations. Here we perform a D&A study via regression of tree ring width (TRW) observations on TRW simulations which are forward modeled from climate simulations. Temperature and moisture-sensitive TRW simulations show distinct patterns in time and space. Temperature-sensitive TRW observations and simulations are significantly correlated for northern hemisphere averages, and their variation is attributed most closely to volcanically forced simulations. In decadally smoothed temporal fingerprints, we find the observed responses to be significantly larger and/or more persistent than the simulated responses. The pattern of simulated TRW of moisture-limited trees is consistent with the observed anomalies in the two years following major volcanic eruptions. We can for the first time attribute this spatiotemporal fingerprint in moisture limited tree-ring records to volcanic forcing. These results suggest that use of nonlinear and multivariate proxy system models in paleoclimatic detection and attribution studies may permit more realistic, spatially resolved and multivariate fingerprint detection studies, and evaluation of the climate sensitivity to external radiative forcing, than has previously been possible.