iHARP: Talk Tuesday by Lauren Andrews
PolarMERRA: A Polar-Focused Global Reanalysis Project
When and where: April 18, 2023, 2023 4p - 5p (est) | Virutal
The adequate modeling of physical processes in the Arctic and Antarctic is vital for developing prediction capabilities and for obtaining an understanding of rapidly evolving polar conditions, including their potential global impacts. These processes are often poorly represented in global models and reanalyses, owing to a legacy modeling focus on midlatitude processes, as well as a scarcity of observations needed for model development in polar regions. The polarMERRA initiative, a joint effort between NASA’s Cryospheric Sciences and Modeling and Prediction programs, seeks to improve the representation of cryospheric and polar atmospheric processes and to develop an open-source framework for a quantitatively evaluation of polar-relevant variables against current and future satellite and in-situ observations, models, and reanalyses.
Here, we evaluate the impacts of spatial resolution and modifications to sea ice, ice sheet, and atmospheric parameterizations on the representation of high latitude conditions by using a quantitative scorecard approach that leverages NASA’s extensive satellite record. Investigations are conducted using the NASA Goddard Earth Observing System model (GEOS) and its data assimilation system (GEOS DAS). Through a quantitative identification of process deficiencies, bias reductions in key surface variables, including temperature and precipitation over cryospheric surfaces, may be achieved. The polarMERRA project additionally seeks to identify additional data sources for use in the GEOS DAS, and to incorporate data and parameterization improvements into future model and reanalysis products for scientific and stakeholder use.
Learn More about Dr. Lauren Andrews
Dr. Lauren Andrews is an earth scientist with the Global Modeling and Assimilation Office (GMAO) at NASA Goddard Space Flight Center (GSFC). Her research focuses on understanding the role of the cryosphere in the Earth system, including how glacial meltwater can alter the dynamic response of ice sheets and glaciers and how the representation of cryospheric processes, including snow and sea ice, can impact sub-seasonal to seasonal forecasting. She is a member of the GMAO Subseasonal-to-Seasonal Prediction Team, and she leads the PolarMERRA Reanalysis Project, a joint effort between GMAO and GSFC Cryospheric Sciences Lab, to produce a high-resolution atmospheric reanalysis focused on the representation of polar regions.