Patterns of Climate Variability

这项资助研究涉及应用各种统计分析工具和动态洞察力来调查从几周到几十年的时间尺度上的气候变化。分析将主要基于观测数据，包括模型同化的数据集，如NCEP和ECMWF再分析。特别令人感兴趣的是主要的变率模式或“模态”，它们占了压力场变化的不成比例的大部分，与ENSO循环相关的观测到的年际变率的强迫模式，以及大气环流的纬向对称（或环状）分量的波动。研究的主要目标是：(1)对这些主要变率模式进行更简洁和动态的分类；(2)更好地理解与一个模态相关的环流异常影响其他模态结构的非线性相互作用；(3)记录这些模式对地表天气、大气二氧化碳浓度、气溶胶、海洋颜色和陆地植被的广泛影响；(4)阐明它们在造成过去几十年观测到的高纬度显著变暖和其他气候趋势中的作用；(5)更一般地说，确定过去几十年的气候趋势是否大到足以解释在阿拉斯加和其他极地和亚极地地区观测到的大的环境变化。该项目将直接支持研究生的培养，并间接促进博士后研究人员的指导。项目成果包括基本大气环流统计的在线地图集和关于大气环流的专著。这项研究很重要，因为它具有教育意义，也因为它提供了与天气和气候预测有关的科学信息。

This grant research involves the application of a variety of statistical analysis tools and dynamical insight to investigate climate variability on time scales ranging from weeks to decades. The analysis will be primarily based on observational data, including model assimilated datasets such as the NCEP and ECMWF Reanalyses. Of particular interest are the principal patterns or 'modes' of variability that account for disproportionately large fractions of the variance of the pressure field, the forced pattern in the year-to-year variability observed in association with the ENSO cycle, and fluctuations in the zonally symmetric (or annular) component of the atmospheric general circulation. The major goals of the research are:(1) to formulate a more concise and dynamically based classification of these leading modes of variability;(2) to better understand the nonlinear interactions by which the circulation anomalies associated with one mode influence the structure of other modes;(3) to document the widespread impacts of these modes upon surface weather, atmospheric carbon dioxide concentrations, aerosols, ocean color, and land vegetation; (4) to elucidate their role in producing the pronounced high latitude warming and other climatic trends that have been observed during the past few decades;(5) more generally, to determine whether the climate trends of the past few decades are large enough to account for the large environmental changes that have been observed over Alaska and other polar and sub-polar regions.The project will directly support the training of graduate students and indirectly contribute to the mentoring of postdoctoral research associates. Project deliverables include an on-line atlas of basic general circulation statistics and a monograph on the atmospheric general circulation.This research is important because of its educational impacts and also because it provides scientific information relevant to weather and climate prediction.