Collaborative Research: P2C2--Paleowind Synthesis of Models and Data to Constrain the Response of Extratropical Atmospheric Circulation to External Forcing

本项目旨在评估数值模式在模拟北半球近地面风方面的能力。近地表风是大尺度大气特征的表面表现，例如由纵向(子午线)和纬度(纬向)温度梯度变化驱动的驻波。未来，由于温室气体浓度上升，预计近地面风将随着温度和大气环流的变化而发生变化。然而，对未来近地面风的预测显示，两个模型之间存在很大的不确定性。研究人员建议通过过去的气候数据-模型合成来评估这种不确定性，以评估模型对观测数据以外的气候驱动因素的响应的保真度。通过研究最后一次冰川最大时期，数据合成和数据模型比较可能会增强对驱动北半球风速和驻波变化的因素的理解。此外，它可能有助于检测可能延伸到未来气候驱动因素的模型偏差。该项目潜在的更广泛的影响包括一种新的风代用记录的应用，以促进对过去大气环流的了解，并改进对未来风变率的预测。该项目将在北半球产生一个古风数据合成，供科学界使用，并将向公众开放。通过这项研究获得的风向和阵风方面的知识可能对未来的风能资源具有潜在的意义。这项研究将从风成气候档案中为末次盛冰期生成新的北半球、温带外古风向合成。从黄土和沙丘按时间顺序约束到LGM的古风向将与参与第三次和第四次古气候模拟国际比较项目的大气环流模式(GCM)的LGM模拟以及瞬变气候演化和同位素启用的瞬变气候演化(TRACE-21K和ITRACE)实验的LGM周期的LGM模拟进行分类比较。这种比较将使研究人员能够根据数据-模型一致性的大小来评估排名靠前和排名靠后的模型中的一般大气环流指标。考虑到数据模型的一致性和定常波的性质，将审查与已知的关于驻波的温度控制的进一步比较，例如赤道到极地的温度梯度和海洋-陆地的对比度，以评估潜在的模型偏差。单次强迫试验、不同冰盖模式的模拟和瞬变消冰模拟将揭示单个强迫因子和冰盖地形在确定LGM近地表风向和驻波特性方面的作用。该项目将支持两名女研究人员的职业生涯和一名研究生的科学培训。此外，研究人员将参与外展活动，重点是为参加伊利诺伊州香槟当地STEAM(科学、技术、工程、艺术和数学)工作室课后计划的小学生开发和实施新的教育模块。在这个以风为重点的关于天气和气候的新模块中，20人的五年级学生班级将向手持Kestrel 1000管乐器，在为期6周的模块期间测量一天中不同时间和不同地点的风。学生们将使用他们自己的测量结果与研究人员讨论天气，特别是风速和风向每天是如何变化的。本单元的顶峰将是实地考察伊利诺伊州埃尔斯沃斯当地的Twin Groves风电场(伊利诺伊州香槟以西)，进行教育导游。该奖项反映了NSF的法定使命，并已通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This project aims to evaluate numerical model skill in simulating near-surface winds in the Northern hemisphere. Near-surface winds are a surface manifestation of large-scale atmospheric features such as stationary waves which are driven by changes in longitudinal (Meridional) and latitudinal (zonal) temperature gradients. In the future, near-surface winds are expected to change in response to changes in temperature and atmospheric circulation as driven by rising greenhouse gas concentrations. However, projections of future near surface winds show a large uncertainty between the models. The researchers propose to evaluate this uncertainty via past climate data-model synthesis to assess the fidelity of model response to climate drivers outside the observational data. By investigating the Last Glacial Maximum (LGM) period, the data synthesis and data-model comparison can potentially enhance the understanding of the factors driving changes in Northern hemisphere wind speeds and stationary waves. Further, it can potentially aid to detect model biases that may extend to future climate drivers. The potential Broader Impacts of this project include a novel application of wind proxy records to advance the understanding of past atmospheric circulation and improve future projections of wind variability. This project will generate a paleowind data synthesis in the Northern Hemisphere that will be available for the scientific community and will be publicly accessible. The gained knowledge through this research in terms of wind direction and gustiness can be potentially relevant to future wind energy resources.The proposed research will produce a new synthesis of Northern Hemisphere, extratropical paleowind direction for the LGM from aeolian climate archives. Inferred paleowind direction from loess and dunes chronologically constrained to the LGM will be categorically compared to near-surface wind directions from the LGM simulations of the general circulation models (GCMs) participating the third and fourth Paleoclimate Modelling Intercomparison Projects and the LGM periods of the Transient Climate Evolution and isotope-enabled Transient Climate Evolution (Trace-21k and iTrace) experiments. This comparison will allow the researchers to evaluate metrics for general atmospheric circulation in the top and bottom-ranking models based on the magnitude of data-model agreement. A further comparison with known temperature controls on stationary waves, e.g., the equator to pole temperature gradient and the ocean-land contrast, will be examined considering data-model agreement and stationary wave properties to assess potential model biases. Simulations from single forcing experiments, experiments using different ice sheet models, and the transient deglacial simulation will reveal the role of individual forcing factors and ice sheet orography in setting LGM near-surface wind direction and stationary wave properties. The project will support the careers of two female researchers and the scientific training of one graduate student. Additionally, the researchers will engage in outreach activities that will focus on developing and implementing a new education module for elementary students attending the local STEAM (Science, Technology, Engineering, Arts, and Math) Studio afterschool program in Champaign, IL. In this new module on weather and climate, with an emphasis on wind, the 20-member 5th grade student class will be given handheld Kestrel 1000 wind instruments to measure wind at different times of day and in different locations during a 6-week module period. The students will discuss with the researchers how weather and particularly, wind speed and direction changes from day to day using their own measurements. The capstone of this module will be a field trip to the local Twin Groves Wind Farm, Ellsworth, IL (west of Champaign, IL) for an educational guided tour.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.