气候变化领域集成服务门户(CCPortal): Assessing CLUBB PDF Closure Assumptions for a Continental Shallow-to-Deep Convective Transition Case Over Multiple Spatial Scales

CCPortal

DOI	10.1029/2020MS002145
	Assessing CLUBB PDF Closure Assumptions for a Continental Shallow-to-Deep Convective Transition Case Over Multiple Spatial Scales
	Huang M.; Xiao H.; Wang M.; Fast J.D.
发表日期	2020
ISSN	19422466
卷号	12 期号:10
英文摘要	Assumed-PDF (probability density function) higher-order turbulence closures (APHOCs) are now widely used for parameterizing boundary layer turbulence and shallow convection in Earth system models (ESMs). A better understanding of the resolution-dependent behavior of APHOCs is essential for improving the performance of next-generation ESMs with intended horizontal resolutions finer than 10 km. In this study, we evaluate the PDF family of Analytic double-Gaussian 1 implemented in Cloud Layers Unified By Binormals (CLUBB) over a range of spatial scales (Dx) from 2 to 100 km. A 120-km-wide large eddy simulation (LES) for a continental convection case during 2016 Holistic Interactions of Shallow Clouds, Aerosols, and Land-Ecosystems (HI-SCALE) field campaign serves as benchmark to evaluate the PDF closure using an off-line approach. We find during the shallow convection period, the CLUBB PDF closure tends to produce positive biases of cloud properties and liquid water flux near cloud base for all scales of analysis. It produces negative biases for these variables near cloud top that are more severe for Dx larger than 25 km. Results show that replacing the CLUBB-parameterized moisture and temperature skewnesses with LES-derived ones can fix most of the biases if clipping of input moments is allowed to prevent the occurrence of unrealizable solutions. Overall, the performance of the PDF closure is better for smaller Dx = 2–5 km than for larger Dx = 50–100 km; for a given grid spacing, it is better when the convective clouds become deeper in the late afternoon. Likely causes for the resolution dependence and implications for improving the PDF closure are discussed. © 2020. The Authors.
英文关键词	parameterization; scale dependence; shallow convection
语种	英语
scopus关键词	Atmospheric thermodynamics; Boundary layers; Large eddy simulation; Turbulence; Boundary layer turbulence; Closure assumptions; Holistic interactions; Horizontal resolution; Off-line approaches; PDF(probability density function); Shallow convection; Turbulence closures; Probability density function; atmospheric convection; benchmarking; boundary layer; Gaussian method; holistic approach; large eddy simulation; parameterization; turbulence; water flux
来源期刊	Journal of Advances in Modeling Earth Systems
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/156600
作者单位	Key Laboratory of Meteorological Disaster, Ministry of Education/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/School of Atmospheric Physics, Nanjing University of Information Science and Technology, Nanjing, China; Atmospheric Sciences and Global Change Division, Pacific Northwest National Laboratory, Richland, WA, United States; School of Atmospheric Sciences, Nanjing University, Nanjing, China; Joint International Research Laboratory of Atmospheric and Earth System Sciences and Institute for Climate and Global Change Research, Nanjing University, Nanjing, China
推荐引用方式 GB/T 7714	Huang M.,Xiao H.,Wang M.,et al. Assessing CLUBB PDF Closure Assumptions for a Continental Shallow-to-Deep Convective Transition Case Over Multiple Spatial Scales[J],2020,12(10).
APA	Huang M.,Xiao H.,Wang M.,&Fast J.D..(2020).Assessing CLUBB PDF Closure Assumptions for a Continental Shallow-to-Deep Convective Transition Case Over Multiple Spatial Scales.Journal of Advances in Modeling Earth Systems,12(10).
MLA	Huang M.,et al."Assessing CLUBB PDF Closure Assumptions for a Continental Shallow-to-Deep Convective Transition Case Over Multiple Spatial Scales".Journal of Advances in Modeling Earth Systems 12.10(2020).