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、南极科学司、海洋与气候系统计划颁发了这一奖项，以支持一系列大气模拟练习，以研究麦克默多干旱山谷地区的气候变异性。适用于极地条件的极地MM5大气模式的各种实施将用来描述当代气候及其控制机制的空间和时间变异性。模型的边界条件将进行调整，以解决这样一个问题：尽管附近的冰芯证据表明，年平均温度比现在低4-8摄氏度，但在最后一次冰盛期期间，比目前大得多的湖泊如何在干燥的山谷中持续存在到全新世。将采用嵌套模拟方法，由南极中尺度预报系统存档的模式运行提供更大规模的条件，该系统是一个以南极洲为重点的协作性实验性数值天气预报项目，分辨率在区域上从60公里到2.2公里不等。为了研究当代的空间和时间变异性，PI将嵌套一个1公里水平分辨率版本的极地MM5，它从地面延伸到平流层，在一整年的间隔中每小时输出一次。从1985年到现在，将使用较小的水平分辨率(2公里)模拟来评估融化季节的年际变化和大尺度(厄尔尼诺-南方涛动和南环状模式)气候相互作用。为了解决古气候问题，将使用末次冰川地形，并调整冰层和湿度以模拟古气候条件。PPI在提案中表明，可以以合乎逻辑的方式调整现有2.2公里的极地MM5实施，以获得与干旱山谷自动气象站观测更一致的结果。这使人们相信，拟议的其他改进措施，包括适当的土地类型描述、减少的模型重新初始化和对遮阳和坡向对太阳辐射量的影响的参数化，将在模拟能力和对干谷气候变异性的理解方面取得重大进展。更广泛的影响：该项目的结果可能会对正在进行的干旱山谷长期生态研究项目产生重要影响。拟议项目的结果将在当地网站上公布，并提供给国家冰雪数据中心，以便更广泛地传播。这项建议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。该项目产生的材料将用于共同促进和平协会的大学讲座，并打算以参观哥伦布公立学校讲座的形式用于外联工作，这些学校的学生机构主要由代表不足的群体组成。与伯德极地研究中心外展协调员的合作旨在为访问该中心的初中生和高中生提供数据和可视化材料，并最终为教师制作LTER DVD。