# Towards Unifying the Planetary Boundary Layer and Shallow Convection in CAM5 with the Eddy-Diffusivity/Mass-Flux Approach

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## Abstract

**:**

## 1. Introduction

## 2. Stochastic Multi-Plume EDMF Scheme

#### 2.1. Mass-Flux Parameterization

#### 2.2. Eddy-Diffusivity Parameterization

## 3. Setup of the Experiments

#### 3.1. Configuration Overview

#### 3.2. Reference Models

## 4. Results: Steady-State Marine Convection

#### 4.1. Thermodynamic Profiles

#### 4.2. Thermodynamic Subgrid Vertical Flux Profiles

#### 4.3. Updraft Properties

## 5. Results: Diurnal Cycle of Continental Convection

#### 5.1. Convective Layer Evolution

#### 5.2. Thermodynamic Profiles

#### 5.3. Parameterized Fluxes of Heat and Moisture

#### 5.4. Updraft Properties

## 6. Summary and Conclusions

## Author Contributions

## Funding

## Acknowledgments

## Conflicts of Interest

## Appendix A. Details of the EDMF Implementation in CAM5

## References

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**Figure 1.**Mean profiles of (left column) liquid water potential temperature and (right column) total water mixing ratio for the BOMEX case, averaged over the last three simulation hours, from the Community Atmosphere Model (CAM) using either the default (SHUW) or the new (EDMF) parameterizations and from LES. Each row represents the results for a different number of model levels as indicated by the title. The cloud base from LES is denoted with dashed gray lines.

**Figure 2.**Mean profiles of the vertical fluxes of (left column) liquid water potential temperature and (right column) the total water mixing ratio for the BOMEX case, averaged over the last three simulation hours, from the CAM model using either the default (SHUW) or the new (EDMF) parameterizations and from LES. The green shading denotes the spread of the LES results. The dashed lines mark the mass flux contribution. Each row represents the results for a different number of model levels as indicated by the title. The cloud base is at around 500 m.

**Figure 3.**Mean profiles of the updraft properties (from left to right): updraft area, vertical velocity, updraft cloud water mixing ratio, total water excess, liquid water potential temperature excess) averaged over the last three hours of simulation, from the CAM model using either the default (SHUW) or the new (EDMF) parameterizations, as well as from LES. The green shading denotes the differences between the LES profiles for cloud cores (continuous lines) and whole clouds (dashed lines). Each row represents the results for a different number of model levels as indicated by the title.

**Figure 4.**Evolutions of the convective cloud base (crosses) and top (dots) heights, from the CAM model using either the default (SHUW) or the new (EDMF) parameterizations, as well as from LES. Each row represents the results for a different number of model levels as indicated by the title.

**Figure 5.**Mean profiles of total water mixing ratio for the ARM case at 14:30, 17:30, 20:30, 23:30 (UTC), averaged over the last three simulation hours, from the CAM model using either the default (SHUW) or the new (EDMF) parameterizations and from LES. Each row represents the results for a different number of model levels as indicated by the title. The cloud base from LES is denoted with gray dashed lines.

**Figure 6.**As in Figure 5, but for liquid water potential temperature.

**Figure 7.**Mean profiles of the fluxes of total water mixing ratio for the ARMcase at 14:30, 17:30, 20:30, and 23:30 UTC, from the CAM model using either the default (SHUW) or the new (EDMF) parameterizations and from LES. The dashed lines denote the mass flux contribution. Each row represents the results for a different number of model levels as indicated by the title.

**Figure 8.**Same as in Figure 7, but for liquid water potential temperature.

**Figure 9.**Mean profiles of the updraft properties (from left to right): updraft area, vertical velocity, updraft cloud water mixing ratio, total water excess, liquid water potential temperature excess) for the ARM case at 18:30 UTC, from the CAM model using either the default (SHUW) or the new (EDMF) parameterizations, as well as from LES. The green shading denotes the range of values from LES between the cloud core (continuous line) and the whole cloud (dashed line). Each row represents the results for a different number of model levels as indicated by the title.

**Figure 10.**Same as in Figure 9, but at 20:30 UTC.

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**MDPI and ACS Style**

J. Kurowski, M.; Thrastarson, H.T.; Suselj, K.; Teixeira, J.
Towards Unifying the Planetary Boundary Layer and Shallow Convection in CAM5 with the Eddy-Diffusivity/Mass-Flux Approach. *Atmosphere* **2019**, *10*, 484.
https://doi.org/10.3390/atmos10090484

**AMA Style**

J. Kurowski M, Thrastarson HT, Suselj K, Teixeira J.
Towards Unifying the Planetary Boundary Layer and Shallow Convection in CAM5 with the Eddy-Diffusivity/Mass-Flux Approach. *Atmosphere*. 2019; 10(9):484.
https://doi.org/10.3390/atmos10090484

**Chicago/Turabian Style**

J. Kurowski, Marcin, Heidar Th. Thrastarson, Kay Suselj, and Joao Teixeira.
2019. "Towards Unifying the Planetary Boundary Layer and Shallow Convection in CAM5 with the Eddy-Diffusivity/Mass-Flux Approach" *Atmosphere* 10, no. 9: 484.
https://doi.org/10.3390/atmos10090484