Tracking the movement and strength of the Northern Hemisphere westerlies over the last glacial cycle.

追踪上一次冰期期间北半球西风的运动和强度。

• 批准号: 2103037
• 负责人: Gisela Winckler
• 金额: $ 29.78万
• 依托单位: Columbia University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-07-15 至 2024-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2103037&HistoricalAwards=false
• 关键词: Tracking; movement; strength; Northern; Hemisphere

The westerly wind belts are a key part of the climate system. Knowing the strength and position of the westerlies during different climate states and across abrupt shifts in climate would provide insight into the mechanisms of climate variability. Studying the westerlies during past warm intervals is particularly important because modern observations of weather patterns suggest that the westerly winds are moving poleward in response to global warming. The proposed study will document the strength and position of the Northern Hemisphere westerlies using sediment records of dust accumulation and upper ocean biological productivity. Sediment cores from sites in the North Pacific Ocean will cover the last 150,000 years. They will include the most recent global warm interval roughly 130,000 to 115,000 years ago. The Broader Impacts of the proposed study include support for a postdoctoral fellow. The study also will provide opportunities for including high school students in hands-on research through the Lamont High school Intern Program. That program builds on existing partnerships with New York City and Rockland County high schools to recruit students from groups underrepresented in the earth sciences. This proposed study will produce five ~150 kyr dust, productivity, and grain size records from the North Pacific Ocean to characterize the westerly winds during various mean climate states (peak interglacials of MIS 5e and the Holocene as well as peak glacials of MIS 6 and the last glacial maximum), and how they respond to abrupt climate changes during Terminations I and II. These records will use samples from five marine sediment cores from a recent RV Sonne research cruise to the North Pacific (SO264) that encompass ~15° latitude. These data will fill a gap in the current picture of a key region in the Northern Hemisphere and will serve as benchmarks for modeling studies. These datasets will be useful to both the paleoclimate and modern/future climate modeling fields, as they will provide constraints on the natural variability of the westerlies to changes in potential driving mechanisms such as ice volume and atmospheric temperature gradients, thus aiding essential modeling of future changes in the westerly winds. Finally, the results of this work could serve as the impetus to perform similar studies in other regions of the world, such as the Southern Hemisphere, allowing questions related to hemispheric synchroneity of atmospheric circulation across various climate regimes to be addressed. The PI is the co-chair of the new Lamont LDEI Task Force and is deeply involved in implementing diversity programs on all levels, including active recruitment of underrepresented minorities in the Geosciences. Interpretations and conclusions drawn from this work will be brought to the public via non-technical settings such as the annual Lamont-Doherty Open House.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

西风带是气候系统的关键部分，了解不同气候状态和气候突变期间西风带的强度和位置将有助于深入了解过去温暖时期的西风带机制。重要的是，因为现代对天气模式的观测表明，由于全球变暖，西风正在向极地移动。拟议的研究将利用灰尘积累和上层海洋沉积物的沉积记录来记录北半球西风的强度和位置。北太平洋地点的岩心将涵盖过去 15 万年的数据，其中包括大约 13 万至 115,000 年前的最近一次全球变暖。该研究的更广泛影响还包括为博士后研究员提供支持。通过拉蒙特高中实习生计划让高中生参与实践研究的机会该计划建立在与纽约市和罗克兰县高中现有的合作伙伴关系的基础上，从团体中招收学生。这项拟议的研究将产生来自北太平洋的 5 个约 150 kyr 的尘埃、生产力和颗粒尺寸记录，以表征各种平均气候状态（MIS 5e 和全新世的峰值间冰期以及MIS 6 的峰期冰川和末次盛冰期），以及它们如何应对终端 I 和 II 期间的突然气候变化。这些记录将使用来自最近 RV 的五个海洋沉积物岩心的样本。 Sonne 研究航行覆盖约 15° 纬度的北太平洋（SO264），这些数据将填补北半球关键区域当前​​情况的空白，并将作为建模研究的基准。古气候和现代/未来气候建模领域，因为它们将为西风带的自然变化对冰量和大气温度梯度等潜在驱动机制的变化提供限制，从而有助于对未来变化进行基本建模最后，这项工作的结果可以推动在世界其他地区（例如南半球）进行类似的研究，从而解决与不同气候状况下的半球大气环流同步性相关的问题。是新的拉蒙特 LDEI 工作组的联合主席，深入参与各个层面的多样性计划的实施，包括积极招募地球科学领域代表性不足的少数群体。将通过年度 Lamont-Doherty 开放日等非技术环境向公众展示。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。