RAPID: Decadal Variability of the American Monsoons--An Assessment of CMIP5 Simulation

这是16个快速反应（RAPID）项目之一，作为亲爱的同事信（NSF 11-006）的结果，鼓励对政府间气候变化专门委员会第五次评估报告（IPCC AR 5）准备的气候模型模拟进行诊断分析。在这些项目中进行的研究预计将导致更详细的模式相互比较，更好地理解强大的模式行为，更好地理解和量化的不确定性，在未来的气候模拟。这个项目检查模拟的美国季风系统（AMS）在最近的过去从气候模式相互比较项目版本5（CMIP 5）。 其主要目标是发展一个广泛的评估，如何现实的模拟是在代表美国季风系统（AMS）的观测特征，在最近的过去，并评估在AMS预测的十年气候变化的不确定性。更具体地说，该项目1）评估CMIP 5模式模拟美洲季风气候和统计特征的能力，包括：环流和降水特征，亚季节变化，爆发和消亡，振幅和跨赤道转换。2）确定哪些CMIP 5模式真实地代表了当前气候中季风的时空变化，包括近期趋势，极端降水事件的统计分布和极端干湿季节的频率。3）检验CMIP 5模式是否能很好地反映远程强迫与美国季风之间的关系。这些包括马登-朱利安涛动（MJO）、厄尔尼诺/南方涛动（ENSO）、北大西洋涛动（NAO）、太平洋十年涛动（PDO）、南极涛动（AAO）、大西洋和美洲海强迫力。试图确定美洲未来几十年预测的气候变化中有多少是由自然年代际变率解释的，有多少是由温室气体增加解释的。该项目的影响在于它对气专委第五次评估报告的支持，该报告旨在向全世界的决策者提供关于气候变化及其后果的信息。 AMS影响到美洲人口稠密的大片地区的水资源、农业、人类健康、生态系统和生物多样性。 气候变化对AMS的影响尚不清楚，这项研究将有助于确定用于预测气候变化的模型在多大程度上能够准确地反映AMS系统及其在观测记录上的变异性和变化。

This is one of 16 Rapid Response (RAPID) projects funded as the result of a Dear Colleague Letter (NSF 11-006) encouraging diagnostic analyses of climate model simulations prepared for the Intergovernmental Panel on Climate Change Fifth Assessment Report (IPCC AR5). Research conducted in these projects is expected to lead to more detailed model intercomparisons, better understanding of robust model behaviors, and better understanding and quantification of uncertainty in future climate simulations.This project examines the simulation of the American Monsoon System (AMS) in simulations of the recent past from the Climate Model Intercomparison Project verson 5 (CMIP5). The main goals are to develop an extensive assessment of how realistic simulations are in representing the observed characteristics of the American Monsoon System (AMS) in the recent past, and to assess uncertainties in projected decadal climate changes in the AMS. More specifically, the project1) Assesses the skill of CMIP5 model simulations in representing the climatological and statistical characteristics of the monsoons in the Americas including: circulation and precipitation features, subseasonal variance, onsets and demises, amplitudes and cross equatorial transitions.2) Determines which CMIP5 models realistically represent the spatiotemporal variability of the monsoons in the present climate including near-term trends, frequency of very dry/wet seasons and statistical distributions of extreme precipitation events.3) Examines which CMIP5 models skillfully represent the observed relationships between remote forcings and the American monsoons. These include the Madden-Julian Oscillation (MJO), El Niño/Southern Oscillation (ENSO), North Atlantic Oscillation (NAO), Pacific Decadal Oscillation (PDO), Antarctic Oscillation (AAO), Atlantic Ocean and Intra-Americas Sea forcings.4) Seeks to determine how much of the climate changes projected for the next decades in the Americas are explained by natural decadal variability and how much by greenhouse gases increases.The broader impact of the project lies in its support of the IPCC AR5, which is intended to provide information on climate change and its consequences to decision makers worldwide. The AMS affects water resources, agriculture, human health, ecosystems and biodiversity throughout a large and densely populated portion of the Americas. The impact of climate change on the AMS is not known, and this research will help to determine the extent to which models used to project climate change are capable of accurately representing the AMS system and its variability and change over the observed record.