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arXiv 1607.01529physics.ao-ph
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近期气候变率驱动因素的定量评价:信息论方法

Quantitative assessment of drivers of recent climate variability: An information theoretic approach

Ankush Bhaskar, Durbha Sai Ramesh, Geeta Vichare, Triven Koganti, S. Gurubaran

摘要:

确定和量化近期气候变异的可能驱动因素仍然是一项具有挑战性的任务。这个重要的问题是解决采用非参数信息理论技术,转移熵及其归一化的变体。它清楚地量化了任何两个变量之间随着信息的定向流动而交换的实际信息,与它们的共同历史或输入无关,不像相关性、互信息等。利用1984 - 2005年的厄尔尼诺南方涛动(ENSO)和全球平均气温距平(GMTA)资料,对气候驱动信号和响应信号进行了识别。对它们的相对贡献的估计表明,CO2(~24%),CH4(~19%)和火山气溶胶(~23%)是观测到的GMTA变化的主要贡献者。虽然紫外线(~9%)和厄尔尼诺/南方涛动(~12%)是GMTA变化的次要驱动因素,但其余因素在观测到的近期气候变率中发挥的作用很小。有趣的是,ENSO和GMTA在不同的时间滞后相互驱动。这项研究有助于气候科学未来的建模工作。

英文摘要:

Identification and quantification of possible drivers of recent climate variability remain a challenging task. This important issue is addressed adopting a non-parametric information theory technique, the Transfer Entropy and its normalized variant. It distinctly quantifies actual information exchanged along with the directional flow of information between any two variables with no bearing on their common history or inputs, unlike correlation, mutual information etc. Measurements of greenhouse gases, CO2, CH4, and N2O; volcanic aerosols; solar activity: UV radiation, total solar irradiance (TSI ) and cosmic ray flux (CR); El Nino Southern Oscillation (ENSO) and Global Mean Temperature Anomaly (GMTA) made during 1984-2005 are utilized to distinguish driving and responding climate signals. Estimates of their relative contributions reveal that CO 2 (~24%), CH 4 (~19%) and volcanic aerosols (~23%) are the primary contributors to the observed variations in GMTA. While, UV (~9%) and ENSO (~12%) act as secondary drivers of variations in the GMTA, the remaining play a marginal role in the observed recent climate variability. Interestingly, ENSO and GMTA mutually drive each other at varied time lags. This study assists future modelling efforts in climate science.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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