Collaborative Research: Toward reanalysis of the Arctic Climate System - sea ice and ocean reconstruction with data assimilation

项目摘要标题：对北极气候系统的再分析——海冰和海洋的数据同化重建项目建议为北极冰-海洋系统开发一套综合同化程序，能够提供物理上一致的网格数据集，并受限于海冰和海洋参数的历史观测。基于他们过去在海冰和海洋数据同化方面的研究活动，他们建议为创建北极气候系统再分析迈出一些第一步，该分析使用现代四维变分数据同化方法，采用新的数据同化程序，最大限度地将模式结果与观测结果结合起来。他们将把注意力集中在三个不同的时期，每个时期都代表着北极气候的不同状态。第一个时期是1972-1978年，当时北极相对寒冷，有大量的水文资料可用；第二个时期是1989-1996年，北冰洋环流、水文结构和海冰状况开始发生重大变化；第三个时期是1997年，夏末开始出现大量开放水域。将AOMIP模型得到的场与新的再分析产品进行对比，验证AOMIP模型的结果。在获得与观测结果最拟合的重建解后，他们将重点分析这些时期的海冰、水循环和海洋水文。知识价值：了解北极系统及其变化是SEARCH计划的一个重要目标。与点观测相一致并受点观测约束的准确网格化大气、冰冻圈和海洋场对于了解过去北极变化的起源非常重要，对于形成诸如热量和淡水通量等气候变量的准确预算至关重要。数据同化方法的实际实施对于正确理解和模拟气候系统是必要的，本项目将利用现代技术提供尽可能最准确的结果。这些新的模拟将有助于回答SEARCH、SBI和FWI项目的各种科学问题，并将为ASOF和CLIVAR处理气候研究的国家和国际组成部分做出重大贡献。在该项目中测试和验证的算法也可以应用于2007-2009国际极地年期间对北冰洋的再分析，并将用于SEARCH、DAMOCLES、COME、COME等现有和计划中的活动。更广泛的影响：数据将通过一个网站提供，该网站将包括与其他相关项目和数据的链接，并将被设计为对包括科学界、学生和公众在内的各种受众有用。对研究结果的解释将发表在科学和大众期刊上。该项目的教育活动将包括培训USM和IARC的研究生和本科生，以及将材料整合到西澳大学、USM和UAF的课程中。我们将继续与费尔班克斯和法尔茅斯地区的小学积极接触，并广泛参与在西雅图太平洋科学中心举行的极地科学周末活动。

PROJECT ABSTRACTTitle: Toward reanalysis of the Arctic Climate System - sea ice and ocean reconstruction with data assimilationThe PI's propose to develop an integrated set of assimilation procedures for the arctic ice-ocean system that are able to provide gridded data sets that are physically consistent and constrained to the historical observations of sea ice and ocean parameters. Building on their past research activities in sea ice and ocean data assimilation, they propose to make some first steps toward the creation of an Arctic Climate System Reanalysis that uses modern four-dimensional variational data assimilation methods employing new data assimilation procedures to maximize the integration of model results with observations. They will focus their attention on three distinct periods, each representing a different state of the Arctic climate. The first period is 1972-1978 when the Arctic was relatively cold and there is a large quantity of hydrographic data available, the second is 1989-1996 when large changes begin in the Arctic Ocean circulation, in its hydrographic structure, and in sea ice conditions, and the third is 1997- present when substantial amounts of open water begin to appear in the late summer. Comparison will be made with new reanalysis products with fields obtained by AOMIP models to validate AOMIP model results. After obtaining the reconstructed solutions with the best fit to the observations, they will focus on the analysis of the sea ice, water circulation, and ocean hydrography during these periods.Intellectual Merit: Understanding of the Arctic system and its change is an important goal of the SEARCH program. Accurate gridded atmospheric, cryospheric and oceanic fields consistent with and constrained by point observations are important to understanding the origin of past Arctic changes and are essential for forming accurate budgets of climate variables such as heat and freshwater fluxes. Practical implementation of data assimilation methods is necessary to properly understand and model the climate system, and this project will provide the most accurate results possible with modern techniques. These new simulations will help answer a variety of scientific questions of the SEARCH, SBI, and FWI projects and will significantly contribute to national and international components of ASOF and CLIVAR dealing with climate studies. The algorithms tested and validated in this project could also be applied to a reanalysis of the Arctic Ocean during the 2007-2009 IPY and will be used in existing and planned activities of SEARCH, DAMOCLES, COME, CAME and others.Broader Impact: Data will be available through a web site that will include links to other relevant projects and data, and will be designed to be useful for a variety of audiences including the scientific community, students, and the general public. Interpretations of the results will be published in scientific and popular journals. Educational activities within the project will include training of graduate and undergraduate students at USM and IARC, as well as integration of the material into courses taught at UW, USM and UAF. Active outreach to grade schools in the Fairbanks and Falmouth area and extensive participation in the Polar Science Weekend at the Pacific Science Center in Seattle will continue.