skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Influence of Superparameterization and a Higher-Order Turbulence Closure on Rainfall Bias Over Amazonia in Community Atmosphere Model Version 5: How Parameterization Changes Rainfall

Abstract

We evaluate the Community Atmosphere Model Version 5 (CAM5) with a higher-order turbulence closure scheme, named Cloud Layers Unified By Binomials (CLUBB), and a Multiscale Modeling Framework (MMF) with two different microphysics configurations to investigate their influences on rainfall simulations over Southern Amazonia. The two different microphysics configurations in MMF are the one-moment cloud microphysics without aerosol treatment (SAM1MOM) and two-moment cloud microphysics coupled with aerosol treatment (SAM2MOM). Results show that both MMF-SAM2MOM and CLUBB effectively reduce the low biases of rainfall, mainly during the wet season. The CLUBB reduces low biases of humidity in the lower troposphere with further reduced shallow clouds. The latter enables more surface solar flux, leading to stronger convection and more rainfall. MMF, especially MMF-SAM2MOM, unstablizes the atmosphere with more moisture and higher atmospheric temperatures in the atmospheric boundary layer, allowing the growth of more extreme convection and further generating more deep convection. MMF-SAM2MOM significantly increases rainfall in the afternoon, but it does not reduce the early bias of the diurnal rainfall peak; LUBB, on the other hand, delays the afternoon peak time and produces more precipitation in the early morning, due to more realistic gradual transition between shallow and deep convection. MMF appears tomore » be able to realistically capture the observed increase of relative humidity prior to deep convection, especially with its two-moment configuration. In contrast, in CAM5 and CAM5 with CLUBB, occurrence of deep convection in these models appears to be a result of stronger heating rather than higher relative humidity.« less

Authors:
ORCiD logo [1]; ORCiD logo [2];  [1]; ORCiD logo [3]; ORCiD logo [4]; ORCiD logo [3]; ORCiD logo [1]; ORCiD logo [5]
  1. Jackson School of Geosciences, University of Texas at Austin, Austin TX USA
  2. Jackson School of Geosciences, University of Texas at Austin, Austin TX USA; Department of Atmospheric and Oceanic Sciences, University of California, Los Angeles CA USA
  3. Pacific Northwest National Laboratory, Richland WA USA
  4. Institute for Climate and Global Change Research and School of Atmospheric Sciences, Nanjing University, Nanjing China; Collaborative Innovation Center of Climate Change, Nanjing China
  5. Centro Nacional de Monitoramento e Alertas aos Desastres Naturais, São Jose dos Campos Brazil
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1406792
Report Number(s):
PNNL-SA-123731
Journal ID: ISSN 2169-897X; KP1703010; KP1703040
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Geophysical Research: Atmospheres; Journal Volume: 122; Journal Issue: 18
Country of Publication:
United States
Language:
English
Subject:
58 GEOSCIENCES

Citation Formats

Zhang, Kai, Fu, Rong, Shaikh, Muhammad J., Ghan, Steven, Wang, Minghuai, Leung, L. Ruby, Dickinson, Robert E., and Marengo, Jose. Influence of Superparameterization and a Higher-Order Turbulence Closure on Rainfall Bias Over Amazonia in Community Atmosphere Model Version 5: How Parameterization Changes Rainfall. United States: N. p., 2017. Web. doi:10.1002/2017JD026576.
Zhang, Kai, Fu, Rong, Shaikh, Muhammad J., Ghan, Steven, Wang, Minghuai, Leung, L. Ruby, Dickinson, Robert E., & Marengo, Jose. Influence of Superparameterization and a Higher-Order Turbulence Closure on Rainfall Bias Over Amazonia in Community Atmosphere Model Version 5: How Parameterization Changes Rainfall. United States. doi:10.1002/2017JD026576.
Zhang, Kai, Fu, Rong, Shaikh, Muhammad J., Ghan, Steven, Wang, Minghuai, Leung, L. Ruby, Dickinson, Robert E., and Marengo, Jose. Thu . "Influence of Superparameterization and a Higher-Order Turbulence Closure on Rainfall Bias Over Amazonia in Community Atmosphere Model Version 5: How Parameterization Changes Rainfall". United States. doi:10.1002/2017JD026576.
@article{osti_1406792,
title = {Influence of Superparameterization and a Higher-Order Turbulence Closure on Rainfall Bias Over Amazonia in Community Atmosphere Model Version 5: How Parameterization Changes Rainfall},
author = {Zhang, Kai and Fu, Rong and Shaikh, Muhammad J. and Ghan, Steven and Wang, Minghuai and Leung, L. Ruby and Dickinson, Robert E. and Marengo, Jose},
abstractNote = {We evaluate the Community Atmosphere Model Version 5 (CAM5) with a higher-order turbulence closure scheme, named Cloud Layers Unified By Binomials (CLUBB), and a Multiscale Modeling Framework (MMF) with two different microphysics configurations to investigate their influences on rainfall simulations over Southern Amazonia. The two different microphysics configurations in MMF are the one-moment cloud microphysics without aerosol treatment (SAM1MOM) and two-moment cloud microphysics coupled with aerosol treatment (SAM2MOM). Results show that both MMF-SAM2MOM and CLUBB effectively reduce the low biases of rainfall, mainly during the wet season. The CLUBB reduces low biases of humidity in the lower troposphere with further reduced shallow clouds. The latter enables more surface solar flux, leading to stronger convection and more rainfall. MMF, especially MMF-SAM2MOM, unstablizes the atmosphere with more moisture and higher atmospheric temperatures in the atmospheric boundary layer, allowing the growth of more extreme convection and further generating more deep convection. MMF-SAM2MOM significantly increases rainfall in the afternoon, but it does not reduce the early bias of the diurnal rainfall peak; LUBB, on the other hand, delays the afternoon peak time and produces more precipitation in the early morning, due to more realistic gradual transition between shallow and deep convection. MMF appears to be able to realistically capture the observed increase of relative humidity prior to deep convection, especially with its two-moment configuration. In contrast, in CAM5 and CAM5 with CLUBB, occurrence of deep convection in these models appears to be a result of stronger heating rather than higher relative humidity.},
doi = {10.1002/2017JD026576},
journal = {Journal of Geophysical Research: Atmospheres},
number = 18,
volume = 122,
place = {United States},
year = {Thu Sep 21 00:00:00 EDT 2017},
month = {Thu Sep 21 00:00:00 EDT 2017}
}