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, 
- competed, 
- in progress, 
- not done
Overview table for the owner and an approver of this feature
1.Description | Ozone (O3v2) |
| 2.Owner | Qi Tang |
| 3.Created | |
| 4.Equ | |
| 5.Ver | |
| 6.Perf | |
| 7.Val | |
| 8.Approver | |
| 9.Approved Date | |
| V2.0 |
Title: Improved ozone (O3v2)
Requirements and Design
E3SM Watercycle Group
Date:
Summary
Requirements
Requirement: minor changes in the Linoz module and some related physics code
Date last modified:
Contributors: Qi Tang, Juno Hsu (Unlicensed), Michael J Prather
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
Design solution: Add the ozone sink by applying an e-folding decay to 30 ppb with a 2-day time scale within the four lowermost layers of the atmosphere. Turn off the code that resets the ozone values to climatological values in the troposphere. Also take ozone off from the dry deposition list.
Date last modified:
Contributors: Qi Tang, Juno Hsu (Unlicensed), Michael J Prather
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: Pull requests implemented O3v2 (https://github.com/E3SM-Project/E3SM/pull/3047)
Date last modified:
Contributors: Qi Tang, Juno Hsu (Unlicensed), Michael J Prather
Planned Verification and Unit Testing
Verification and Unit Testing: 5-year and 20-year tests
Date last modified:
Contributors: Qi Tang, Juno Hsu (Unlicensed), Michael J Prather
A 5-year test run with O3v2 is first implemented and compared with the 5-year control run with the ozone in E3SMv1. The climates of these two runs remain very similar. The magnitude of the O3v2 tropospheric loss looks reasonable and approaches a state balancing the stratospheric influx within a couple of months from an initial state taken from O3v1. An extended 20-year test further confirms that the O3v2 is implemented correctly and produces the expected results.
Planned Validation Testing
Validation Testing: 20-year test and 4x CO2 simulation
Date last modified:
Contributors: Qi Tang
The 20-year simulation is complete (as mentioned above). It verifies that the code is implemented correctly and the results are reasonable. A 4x CO2 is planned to examine the climate sensitivity changes.
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)
How will XXX be tested? i.e. how will be we know when we have met requirement XXX. Will these unit tests be included in the ongoing going forward?