Investigation of the Contemporary and Paleo Climates of the McMurdo Dry Valleys, Antarctica

南极洲麦克默多干谷的当代和古气候调查

• 批准号: 0636523
• 负责人: David Bromwich
• 金额: --
• 依托单位: Ohio State University Research Foundation -DO NOT USE
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-07-01 至 2011-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0636523&HistoricalAwards=false
• 关键词: Investigation; Contemporary; Paleo; Climates; McMurdo

The Office of Polar Program, Antarctic Science Divison, Ocean & Climate Systems Program has made this award to suppport a series of atmospheric modeling exercises for examining climate variability in the McMurdo Dry Valleys region. Various implementations of the Polar MM5 atmospheric model that has been adapted for polar conditions will be used to characterize spatial and temporal variability of the contemporary climate and its controlling mechanisms. Boundary conditions for the model will be adjusted to address the question of how lakes much larger than the current ones persisted in the Dry Valleys during the last Glacial Maximum and into the Holocene despite nearby ice core evidence suggesting an annual mean temperature 4-8 degree C cooler than present. A nested modeling approach will be undertaken with larger scale conditions provided by archived model runs from the Antarctic Mesoscale Prediction System that is a collaborative experimental numerical weather forecasting project focused on Antarctica and having resolution that varies regionally from 60-km to 2.2-km. To study contemporary spatial and temporal variability, the PI will nest a 1-km horizontal resolution version of Polar MM5 that extends in 32 levels from the surface to the stratosphere with output at hourly intervals for a full year interval. Interannual variability and larger-scale (El Nino-Southern Oscillation and the Southern Annular Mode) climate interactions will be assessed over the melt season with lesser horizontal resolution (2-km) simulations from 1985 to the present. To address the paleo question, the LGM topography will be employed and ice and humidity adjusted to simulate paleo conditions. The PI demonstrated in the proposal that an existing 2.2-km implementation of Polar MM5 could be adjusted in logical ways to obtain closer agreement with Automatic Weather Station observations in the Dry Valleys. This lends confidence that proposed additional improvements including proper land type depiction, reduced model reinitializations and parameterizing the effects of shading and slope aspect on the amount of solar radiation will result significant progress in modeling capabilities and understanding of Dry Valley climate variability. Broader impacts: The outcome of this project could have important implications for ongoing Long-Term Ecological Research projects in the Dry Valleys. Results from the proposed project are to be posted on a local web site and given to the National Snow & Ice Data Center for broader dissemination. This proposal constitutes the first NSF support obtained by the PI who currently has postdoctoral status at Ohio State University hence it provides early career support. The material generated by this project will be used in university lectures by the co-PI and it is intended to be used in outreach efforts in the form of visits with lectures to Columbus Public Schools whose student bodies are made of a dominant fraction of underrepresented groups. Collaboration with the Byrd Polar Research Center outreach coordinator is intended to yield data and visualization materials for middle and high school student visitors to the Center and eventually an LTER DVD intended for teachers.

极地计划办公室、南极科学部、海洋与气候系统计划颁发此奖项是为了支持一系列大气建模练习，以检查麦克默多干谷地区的气候变化。针对极地条件进行了调整的 Polar MM5 大气模型的各种实施将用于表征当代气候及其控制机制的空间和时间变化。 该模型的边界条件将进行调整，以解决以下问题：尽管附近的冰芯证据表明年平均温度为 4-8 摄氏度，但在上一次盛冰期和全新世期间，干谷中比现在大得多的湖泊是如何持续存在的问题比现在凉爽。 嵌套建模方法将在南极中尺度预测系统存档模型运行提供的更大尺度条件下进行，该系统是一个专注于南极洲的协作实验数值天气预报项目，其分辨率随区域变化从 60 公里到 2.2 公里不等。 为了研究当代的空间和时间变化，PI 将嵌套一个 1 公里水平分辨率版本的 Polar MM5，该版本从地表延伸到平流层 32 个级别，并在全年间隔内每小时输出一次。 从 1985 年至今，将通过较小的水平分辨率（2 公里）模拟来评估融化季节的年际变化和更大规模（厄尔尼诺-南方涛动和南方环模）气候相互作用。 为了解决古问题，将采用末次盛冰期地形并调整冰和湿度以模拟古条件。 PI 在提案中证明，可以以合乎逻辑的方式调整现有 2.2 公里的 Polar MM5 实施，以获得与干谷自动气象站观测结果更接近的一致性。 这让我们相信，提出的额外改进措施，包括适当的土地类型描述、减少模型重新初始化以及参数化遮阳和坡向对太阳辐射量的影响，将在建模能力和对干谷气候变化的理解方面取得重大进展。 更广泛的影响：该项目的结果可能对干河谷正在进行的长期生态研究项目产生重要影响。 拟议项目的结果将发布在当地网站上，并提供给国家冰雪数据中心以进行更广泛的传播。 该提案是目前在俄亥俄州立大学拥有博士后身份的 PI 获得的第一个 NSF 支持，因此它提供了早期职业支持。 该项目生成的材料将由联合PI用于大学讲座，并旨在以访问哥伦布公立学校讲座的形式用于外展工作，这些学校的学生群体主要由代表性不足的群体组成。 与伯德极地研究中心外展协调员合作，旨在为中心的中学生和高中生访客提供数据和可视化材料，并最终为教师提供 LTER DVD。