Variability of the Climate System

Schneider, Edwin K. Kinter, James L.全球环境与社会研究所。题目：气候系统的变率该项目包括一系列数值实验，旨在增加对气候系统自然变率的认识。有必要对自然变率进行准确的估计，以确定由外部强迫产生的气候信号并评估气候预测。该研究与TOGA和CLIVAR/ goals的目标相关，并有望为IPCC/USGCRP做出贡献。拟议的研究将确定并实施一项实验程序，以分离和估计大气、陆地和海洋过程对自然气候变率的贡献。将研究的具体过程包括大气混沌、陆地表面随机强迫、海洋混合层随机强迫、海洋/大气耦合混乱、太阳强迫的年循环。结果将通过对一个数值气候模式的变式所作的几十年到一个世纪的数值积分的分析而得到。该模式的基本版本将包括全球大气和海洋环流子模式、陆地表面过程（包括植被和海冰的影响）。首先，确定全交互耦合模式在模拟海温年平均和年周期的误差。将对模型进行修改以减小这些误差的大小。将进行不含通量修正的控制积分来确定平衡气候。在随后的集成中，组件子模型之间的相互作用将受到限制，以便消除或减少大气/陆地和大气/海洋的耦合。这些变化将以不同的组合形式引入，包括以特定的气候海表温度或混合层海洋取代动力海洋，规范气候土壤混合物和积雪，以及消除年循环。限制模式模拟的气候学将是控制集成的气候学。将结果与《自然》进行相互比较，可以估计大气/陆地和大气/海洋相互作用对模拟和实际气候变率的贡献。还将进行相关试验，研究通量校正和海洋初始条件对气候模拟和预测的影响。由通量校正程序引起的自然变率变化将使用平衡模拟进行评估，在平衡模拟中，改进前的完整气候模式经过通量校正，以产生与控制综合相同的气气学。将进行一项实验来估计由于温室强迫的变化而使当前的气候偏离平衡状态。

Abstract ATM-9520579 Schneider, Edwin K. Kinter, James L. Institute of Global Environment and Society Inc. Title: Variability of the Climate System The project consists of a series of numerical experiments designed to increase understanding of the natural variability of the climate system. It is necessary to have accurate estimates of the natural variability to identify climate signals produced by external forcing and to evaluate climate predictions. This research is relevant to the goals of TOGA and CLIVAR/GOALS and is expected to contribute to IPCC/USGCRP. The proposed research will define and carry out an experimental procedure to isolate and estimate the contributions to natural climatic variability from atmospheric, land and oceanic processes. Specific processes that will be examined are atmospheric chaos, stochastic forcing of the land surface, stochastic forcing of the ocean mixed layer, coupled ocean/atmosphere chaos, the annual cycle of solar forcing. Results will be obtained by analysis of several multi-decade to century long numerical integrations made with variants of a numerical climate model. The basic version of the model will include global atmosphere and ocean general circulation submodels, land surface processes including effects due to vegetation, and sea ice. First, the errors of the fully interactive coupled model in simulating the observed annual mean and annual cycle of sea surface temperature will be ascertained. Modifications to the model will be made to reduce the magnitude of these errors. A control integration without flux corrections will be carried out to determine the equilibrium climate. In subsequent integrations the interactions between the component submodels will be restricted in order to either eliminate or reduce atmosphere/land and atmosphere/ocean coupling. The changes, which will be introduced in various combinations, include replacement of the dynamical ocean with a specified climatological sea surface temp erature or by mixed layer ocean, specification of climatological soil mixture and snow cover, and elimination of the annual cycle. The climatology for the restricted model simulations will be that of the control integration. Intercomparsion of the results and Nature will provide estimates of the contributions of the atmosphere/land and atmosphere/ocean interactions to the modeled and actual climate variability. Related experiments will also be done to study the influence of flux correction and oceanic initial conditions in climate simulation and prediction. Changes in natural variability introduced by the flux correction procedure will be evaluated using an equilibrium simulation in which the full climate model before improvement is flux corrected to produce the same climatology as the control integration. An experiment will be done to estimate the departure of the current climate from equilibrium due to the changing greenhouse forcing.