We plan to conduct data analyses on the retrospective NU-WRF/noah-MP regional climate simulations from 2002 2018 covering dry years and wet years over the contiguous US domain. We will conduct the…

The University of Arizona, operating under the Arizona Board of Regents, received a $62,767.29 research grant from a Shared Services Center within a civilian federal agency for a project titled "Improved Understanding of the Coupled Dynamics of Terrestrial Water, Ecosystems, and Climate over the Contiguous United States Using NU-WRF/NOAH-MP." The award, issued on June 16, 2021, with an ultimate completion date of June 15, 2025, supports data analyses on retrospective regional climate simulations spanning 2002 to 2018 across the contiguous U.S. domain, with particular emphasis on hydrological conditions during both dry and wet years. No set-aside designation was applied to this grant.

The project comprises two primary analytical tasks. Task 1 involves comprehensive model evaluation of precipitation, runoff, evapotranspiration, leaf area index, and terrestrial water storage changes by comparing NU-WRF/NOAH-MP simulations against observational datasets including GPCP, USGS Water Watch, MODIS, and GRACE data. Task 2 focuses on analyzing water-recycling dynamics using MERRA-2 reanalysis data to quantify local evapotranspiration contributions to regional precipitation and to calculate water recycling efficiency and precipitation efficiency metrics for the central U.S., with moisture convergence computed from both atmospheric wind and moisture fields and validated against USGS runoff and GRACE terrestrial water storage observations. The work will be performed in Tucson, Arizona.

We plan to conduct data analyses on the retrospective NU-WRF/noah-MP regional climate simulations from 2002 2018 covering dry years and wet years over the contiguous US domain. We will conduct the following tasks of model evaluation and analyses on the modeled regional water cycle. Task 1: we will evaluate the model simulations of precipitation, runoff, ET, LAI, and terrestrial water storage (TWS) change against gpcp, USGS water watch, modis, and grace data, respectively. Task 2: we will analyze the water-recycling ratio to quantify the contribution of local ET to precipitation. We will merra-2 data to analyze the water recycling efficiency, ET / (ET + QIN), and precipitation efficiency, e p / (ET + QIN), where p is precipitation and QIN the atmospheric moisture convergence into the central US. QIN will be computed directly from the merra-2 wind and moisture fields and indirectly from the USGS monthly runoff and grace TWS change data.