A9 Interactions With Surface Models Design Document
- Tanya Reshel
- Renata McCoy
- Susannah Burrows
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 | Interactions with the surface models (Sea Spray organic matter) |
| 2.Owner | |
| 3.Created | |
| 4.Equ | |
| 5.Ver | |
| 6.Perf | |
| 7.Val | |
| 8.Approver | |
| 9.Approved Date | |
| V1.0 | Accepted |
Title: Interactions with the surface models (Sea Spray, DMS)
Requirements and Design
ACME Atmosphere Group
Date:
Summary
The new v1 capability will read in netCDF files containing ocean surface distributions of marine macromolecules (lipids, polysaccharides, and proteins) and produce emissions of a single marine organic aerosol species within MAM4, adding 3 advected tracers to the model.
Requirements
Requirement 1: Calculation of marine organic emissions from offline fields produced from marine biogeochemistry models
Date last modified:
Contributors: Susannah Burrows, Scott Elliott (Unlicensed), Richard Easter (Unlicensed)
Algorithmic Formulations
Design solution 1a: Formulation of relationship between ocean surface organic concentrations and organic mass fraction of emitted sea spray aerosol
Date last modified: Paper published Dec 2014
Contributors: Susannah Burrows, Scott Elliott (Unlicensed), Phil Rasch (pnl.gov)
See Burrows et al., 2014, ACP.
Burrows, S. M., Ogunro, O., Frossard, A. A., Russell, L. M., Rasch, P. J., and Elliott, S. M.: A physically based framework for modeling the organic fractionation of sea spray aerosol from bubble film Langmuir equilibria, Atmos. Chem. Phys., 14, 13601-13629, doi:10.5194/acp-14-13601-2014, 2014.
Design solution 1b: Formulation of assumed relationships between marine organic mass fraction and particle size and mixing state
Date last modified: Aug 2015
Contributors: Susannah Burrows
Some initial testing is documented here: /wiki/spaces/ATM/pages/32374899.
For an initial implementation, organic mass fraction calculated according to Burrows et al (2014) will be assumed to apply directly to Aitken mode and accumulation mode aerosol. Emissions within MAM4 will be implemented as a default configuration, with all marine organics combined into a single species, adding 3 advected tracers to the MAM4 scheme. A switch/parameter will be implemented to control mixing state (internal/external) of accumulation mode emissions.
Design and Implementation
Implementation 1a: Implementation of Burrows et al. 2014 marine organic aerosol emissions with MAM9 aerosols
Date last modified: 09/15/2015
Contributors: Susannah Burrows, Richard Easter (Unlicensed), Xiaohong Liu
New emissions formulation will be implemented within seasalt_model.F90. Organic mass fraction of emitted aerosol will be calculated using static netCDF files describing the distribution of organic molecules in surface ocean water, provided as netCDF files. The distributions will be obtained from low-resolution ACME ocean BGC simulations if available; otherwise, older distributions from POP simulations will be used. Emitted aerosol mass and number will be added to modes 1 (accumulation), 2 (Aitken) and 4 (primary organic), and emitted sea salt mass will be reduced if appropriate (depending on mixing state).
Implementation 1b: Implementation of alternate marine organic aerosol emissions parameterizations
Date last modified: 09/15/2015
Contributors: Susannah Burrows
PR issued containing implementations 1a and 1b:
PR location: https://github.com/ACME-Climate/ACME/pull/415
Planned Verification and Unit Testing
Verification and Unit Testing: Testing of marine sea spray organic matter code
Date last modified:
Contributors: Susannah Burrows, Richard Easter (Unlicensed)
We will confirm that aerosol budgets are accurate and that emissions (as written to history files) are as expected from offline calculations.
Planned Validation Testing
Validation Testing: short-desciption-of-testing-here
Date last modified:
Contributors: Susannah Burrows, Scott Elliott (Unlicensed)
We will compare atmospheric aerosol concentrations against a small observational dataset that we have assembled (and to which we will add more data if needed).
Planned Performance Testing
Performance Testing: Testing performance
Date last modified:
Contributors: Susannah Burrows
The new implementation will add 3 additional (advected) tracers to MAM4, so it will result in a modest increase in computational time. The history files will be increased by 5 new 3-D fields, and 3 new 2-D (emission flux) fields.