Brief Description
From UKCA
Climate Models used by UKCA
The UKCA model runs within the Hadley Centre version of the Unified Model. There are a number of different versions of this climate model at a number of resolutions which are used for UKCA development.
| UM Version | Model | Horizontal Resolution | Vertical Levels | Model Top | Scheme Used |
|---|---|---|---|---|---|
| 6.1 | HadGAM1a | N48 (2.5°×3.75°) | L60 | ~84km | Tropospheric Chemistry |
| 6.1 | HadGAM2 | N48 | L60 | ~84km | Stratospheric Chemistry |
| 6.6.4 | HadGEM2-ES | N96 | L38 | ~40km | Hadley Centre Earth System Model |
| 7.1 | HadGEM3-A | N96 (1.25°×1.875°) | L38 | ~40km | Tropospheric Chemistry |
| 7.3 | HadGEM3-A r2.0 | N96 | L38 | ~40km | Tropospheric Chemistry |
| 7.3 | HadGEM3-A r2.0 | N96 | L63 | ~40km | Tropospheric Chemistry |
| 7.3 | HadGEM3-A r2.0 | N96 | L85 | 85km | Stratospheric Chemistry |
| 7.3 | HadGEM3-A r2.0 | N48 | L60 | ~84km | Stratospheric Chemistry |
| 7.3 | HadGEM3-AO r2.0 | N48 | L60 | ~84km | QUEST Earth System Model |
UKCA: Currently Available Chemistry Schemes
- Standard Tropospheric Chemistry
- Tropospheric Chemistry with Isoprene
- Extended Tropospheric Chemistry (ExtTC)
- Regional Air Quality (RAQ) Chemistry
- Standard Stratospheric Chemistry
- Chemistry of the Stratosphere and Troposphere
UKCA Development Timeline
Short-Term Development
- Stratospheric Chemistry at UM7.3 HadGEM3-A (N96L85 and N48L60) - Luke Abraham
- ASAD Flux Diagnostics at UM7.3 - Luke Abraham
- Improved representation of isoprene oxidation at UM6.1 - Alex Archibald
- Chemistry of Stratosphere and Troposphere - CheST at UM7.3 - Alex Archibald
- Flight track emulator to compare to campaign data at UM7.3 - Paul Telford
- Fast-JX photolysis code validation at UM7.3 - Paul Telford
Medium-Term Development
- HadGEM3-AO UKCA - Luke Abraham
- Satellite emulator, including averaging kernels, to improve validation at UM7.3 - Paul Telford
- Couple mode aerosols and fast-jx code at UM7.3 - Paul Telford and ?
- Shift UKCA emissions from Section 0 (user-defined) to Section 34 - Mohit Dalvi
Long-Term Development
- Coupled UKCA Stratosphere-Troposphere Chemistry with MODE
UKCA: Model Outline
Development of UKCA consists of the following subprojects:
Tropospheric model development
- HadGEM3 at N96L63 and HadGEM2-ES at N96L38
Tropospheric Configuration of UKCA 
(Fiona M. O’Connor)
Stratospheric model development
- HadGEM3 at N96L85/N48L60
- Coupled stratospheric chemistry
Aerosols
- New aerosol species and microphysics
- Aerosol chemistry
New features
- Coupled chemistry, aerosols and climate model
- Based on new dynamics
- Combined troposphere-stratosphere chemistry
- Improved aerosol microphysics and chemistry
- Capability to interact with surface, radiation and biosphere
- Modular structure
