A3 CLUBB MG2 Design Document
- Tanya Reshel
- Renata McCoy
- Shaocheng Xie
- Wuyin Lin
The Design Document page provides a description of the algorithms, implementation and planned testing including unit, verification, validation and performance testing. Please read Step 1.3 Performance Expectations that explains feature documentation requirements from the performance group point of view.
Design Document
In the table below, 4.Equ means Equations and Algorithms, 5.Ver means Verification, 6.Perf - Performance, 7. Val - Validation, 
- completed, 
- in progress, 
- not done
Overview table for the owner and an approver of this feature
1.Description | CLUBBe convective configuration (CLUBB as shallow and turbulence) + MG2 microphysics |
| 2.Owner | Wuyin Lin |
| 3.Created | |
| 4.Equ |
|
| 5.Ver |  |
| 6.Perf | |
| 7.Val | |
| 8.Approver | Shaocheng Xie |
| 9.Approved Date | |
| V1.0 | Accepted |
Title: CLUBB-Shallow + MG2 microphysics
Requirements and Design
ACME Atmosphere Group
Date: 09-14-15
Summary
The Cloud Layers Unified By Binormals (CLUBB) is based on higher-order closure and the assumed subgrid PDF method to provide a unified parameterization for planetary boundary layer turbulence, shallow cumulus convection, and cloud macrophysics, which are currently represented by separate schemes in the ACME-Atmosphere model. The use of multiple joint PDF in the design of CLUBB makes it flexible to represent a variety of cloud regimes. Properly tuned CLUBB is expected to simulate more realistic cloud transition, such as shallow-to-deep transition of convection and stratocumulus to cumulus transition in marine environment, both of which could have profound impact on model simulations at broad spatial and temporal scales. ACME will use the most recent CLUBB that requires the Version 2 of MG microphysics (MG2). MG2's representation of aerosol effects also enables the consideration of aerosol indirect effect involving shallow clouds. CLUBB and MG2 with prognostic precipitation are particularly suitable for high-resolution models. Although the current design only includes CLUBB-shallow, it will pave the way to eventually incorporate CLUBB-deep for a fully-unified representation for all cloud types in a single framework.
Requirements
Requirement 1: Most recent CLUBB and MG2, along with updated cam interface for MG microphysics
Date last modified: 09/14/15
Contributors: Wuyin Lin, Shaocheng Xie, Jin-Ho Yoon (Unlicensed), Vince Larson, Andrew Gettelman (Unlicensed), Pete Bogenschutz,
Requirement 2: Modified Zhang-McFarlane scheme with trigger-memory for testing the coupling with CLUBB
Date last modified: 09/14/15
Contributors: Steve Ghan (Unlicensed), Wuyin Lin, Shaocheng Xie, Former user (Deleted)
Each requirement is to be listed under a ”section” heading, as there will be a one-to-one correspondence between requirements, design, proposed imple- mentation and testing. Requirements should not discuss technical software issues, but rather focus on model capability. To the extent possible, require- ments should be relatively independent of each other, thus allowing a clean design solution, implementation and testing plan.
Algorithmic Formulations
Equations for CLUBB (registration required); Also see Golaz et al 2002; Larson and Golaz 2005. Equations for MG1; updates for MG2
Design solution 1: CLUBB
- Overview of CLUBB's formulation (Golaz et al. 2002)
- Advances to the numerics of CLUBB (Larson and Golaz 2005)
- Compete equations for CLUBB and the numerics (registration required).
Date last modified: 09/14/15
Contributors: Wuyin Lin, Shaocheng Xie, Jin-Ho Yoon (Unlicensed), Vince Larson, Andrew Gettelman (Unlicensed), Pete Bogenschutz,
Design solution 2: MG2 (MG1 + prognostics precipitation + time-substepping of macrophysics)
- Basic equations (MG1, Morrison and Gettelman 2008)
- Modifications to MG1 (Gettelman et al. 2015)
Date last modified: 09/14/15
Contributors: Wuyin Lin, Shaocheng Xie, Jin-Ho Yoon (Unlicensed), Vince Larson, Andrew Gettelman (Unlicensed), Pete Bogenschutz,
For each requirement, there is a design solution that is intended to meet that requirement. Design solutions can include detailed technical discussions of PDEs, algorithms, solvers and similar, as well as technical discussion of performance issues. In general, this section should steer away from a detailed discussion of low-level software issues such as variable declarations, interfaces and sequencing.
Design and Implementation
Implementation 1: CLUBB with improved ENSO and MG2 are implemented based on cam5_3_83
Date last modified: 09/14/15
Contributors: Wuyin Lin, Shaocheng Xie, Jin-Ho Yoon (Unlicensed), Vince Larson, Andrew Gettelman (Unlicensed), Pete Bogenschutz
Implementation 2: Modified Zhang-McFarlane with trigger-memory is implemented based on SciDAC/high-resolution development
Date last modified: 09/14/15
Contributors: Steve Ghan (Unlicensed), Wuyin Lin, Shaocheng Xie, Former user (Deleted)
This section should detail the plan for implementing the design solution for requirement XXX. In general, this section is software-centric with a focus on software implementation. Pseudo code is appropriate in this section. Links to actual source code are appropriate. Project management items, such as svn branches, timelines and staffing are also appropriate. How do we typeset pseudo code?
Planned Verification and Unit Testing
Verification and Unit Testing: short-desciption-of-testing-here
Date last modified:
Contributors: (add your name to this list if it does not appear)
Planned Validation Testing
Validation Testing: short-desciption-of-testing-here
Date last modified:
Contributors: (add your name to this list if it does not appear)
The implementation has been tested for B4B capability with default ACME, tested for consistencies with NCAR simulations for both FV and SE configurations with CLUBBe+MG2. 5-year AMIP simulations and intercomparison with observations and other candidate schemes have also been completed. Primarily AMWG diagnostics are used for validation.
Planned Performance Testing
Performance Testing: short-desciption-of-testing-here
Date last modified:
Contributors: (add your name to this list if it does not appear)
Early results show that CLUBBe (with MG2) improves simulations of spatial distribution of mean precipitation , intensity distribution of tropical precipitation, continental warm-season diurnal precipitation, cloud properties along the GPCI cross section. CLUBBe simulations also tend to reduce double ITCZ bias over the equatorial Eastern Pacific.