. Kinetic Energy and Precipitation Spectrum Evaluation for the GFS Advanced Physics Test

Abstract
To support NOAA’s Environmental Model Center (EMC) in selecting an advanced physics suite for Version 16 of the Global Forecast System (GFS), the Global Model Test Bed (GMTB) tested four configurations of NOAA’s Unified Forecast System. The test involved a collaboration between GMTB, EMC, NOAA Earth System Research Laboratory (ESRL) Global Systems Division, the Naval Research Laboratory, NOAA ESRL Physical Science Division, and the National Center for Atmospheric Research. The four configurations differed in physics suites and dynamical settings such as for diffusion (for more information on the test configuration see the companion poster by Bernardet et al.). As part of the evaluation, spectra of kinetic energy and precipitation were used to show the sensitivity of the resolved and under-resolved modes to changes in the physical parameterizations and dynamical settings used in the four configurations. Using the January 18, 2016 case study, this poster will highlight examples of the capabilities GMTB has developed for using kinetic energy and precipitation spectra in evaluating physics suites. Model results will be compared against observations and theoretical estimates. Results demonstrate that configurations differ in spin-up time, effective resolution, and preferred scales for convective patterns as expressed by vertical velocity and precipitation spectra.