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

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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.