TY - JOUR
T1 - How Does LCL Height Influence Deep Convective Updraft Width?
AU - Mulholland, J. P.
AU - Peters, J. M.
AU - Morrison, H.
N1 - Funding Information:
The authors thank the two anonymous reviewers for their helpful comments and suggestions. The authors thank Bowen Pan, Johana Lambert, and Janice Mulholland for their insightful comments and extremely helpful feedback. The authors specifically thank Bowen Pan and Geoff Marion for coding assistance. The authors acknowledge high‐performance computing support from Cheyenne (doi:10.5065/D6RX99HX) provided by the National Center for Atmospheric Research (NCAR) Computational and Information Systems Laboratory, sponsored by the National Science Foundation (NSF). Funding for this research was supported by NSF Grants AGS‐1928666 and AGS‐1841674 and Department of Energy Atmospheric System Research Grants DE‐SC0020104 and DE‐SC0000246356.
Funding Information:
The authors thank the two anonymous reviewers for their helpful comments and suggestions. The authors thank Bowen Pan, Johana Lambert, and Janice Mulholland for their insightful comments and extremely helpful feedback. The authors specifically thank Bowen Pan and Geoff Marion for coding assistance. The authors acknowledge high-performance computing support from Cheyenne (doi:10.5065/D6RX99HX) provided by the National Center for Atmospheric Research (NCAR) Computational and Information Systems Laboratory, sponsored by the National Science Foundation (NSF). Funding for this research was supported by NSF Grants AGS-1928666 and AGS-1841674 and Department of Energy Atmospheric System Research Grants DE-SC0020104 and DE-SC0000246356.
Publisher Copyright:
© 2021. American Geophysical Union. All Rights Reserved.
PY - 2021/7
Y1 - 2021/7
N2 - Previous studies have hypothesized that the width of deep convection should positively scale with lifting condensation level (LCL) height. To evaluate this hypothesis, we analyzed idealized large-eddy simulations with varying LCL heights and initial warm bubble widths in unsheared environments with comparable convective available potential energy. For a given initial warm bubble width, simulations with higher LCLs result in wider, deeper, and stronger cloudy updrafts compared to simulations with lower LCLs. Rising dry thermals in higher LCL simulations experience longer residence times within the sub-cloud layer, and consequently entrain more conditionally unstable air and grow wider before reaching the LCL. The resulting cloudy updrafts are wider, deeper, and have faster vertical velocities because of a reduction in entrainment-driven dilution of buoyancy, relative to lower LCL simulations. These results confirm the hypothesized positive relationship between LCL height and deep convective updraft width, and provide a physical explanation for this relationship.
AB - Previous studies have hypothesized that the width of deep convection should positively scale with lifting condensation level (LCL) height. To evaluate this hypothesis, we analyzed idealized large-eddy simulations with varying LCL heights and initial warm bubble widths in unsheared environments with comparable convective available potential energy. For a given initial warm bubble width, simulations with higher LCLs result in wider, deeper, and stronger cloudy updrafts compared to simulations with lower LCLs. Rising dry thermals in higher LCL simulations experience longer residence times within the sub-cloud layer, and consequently entrain more conditionally unstable air and grow wider before reaching the LCL. The resulting cloudy updrafts are wider, deeper, and have faster vertical velocities because of a reduction in entrainment-driven dilution of buoyancy, relative to lower LCL simulations. These results confirm the hypothesized positive relationship between LCL height and deep convective updraft width, and provide a physical explanation for this relationship.
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U2 - 10.1029/2021GL093316
DO - 10.1029/2021GL093316
M3 - Article
AN - SCOPUS:85109775120
SN - 0094-8276
VL - 48
JO - Geophysical Research Letters
JF - Geophysical Research Letters
IS - 13
M1 - e2021GL093316
ER -