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 Aerosol Scheme: GLOMAP-mode
- Brief summary of GLOMAP-mode: global size-resolved aerosol microphysics
- GLOMAP-mode in UKCA linked to Tropospheric Chemistry (StdTrop)
- GLOMAP-mode in UKCA linked to Tropospheric Chemistry (IsopTrop)
- GLOMAP-mode in UKCA linked to Stratospheric Chemistry (StratChem)
- GLOMAP-mode in UKCA linked to whole-atmosphere chemistry (CheST)
- Direct effect from GLOMAP-mode aerosol to the Edwards-Slingo radiation scheme
- First indirect effect from GLOMAP-mode aerosol to the Edwards-Slingo radiation scheme
Nudging
- Description of the nudged version of UKCA: This describes the nudged version of the model which is constrained to meteorological analysis data, allowing hindcasts and comparisons to episodic data-sets.
UKCA Development Timeline
If you are interested in using UKCA, and there is a particular piece of functionality that you would like or need, but are not sure if it is available, please contact Luke Abraham for further information.
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
- Emissions Profiling from ExTC at 7.3- Paul Telford & Maria Russo
- Interactive biogenic emissions from ExTC at 7.3- 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 Sec34 emissions
- Extend Weseley scheme dry deposition to match 2D scheme - Paul Telford
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
- Integrated Climate Programme report (Mar10) comparing CLASSIC and GLOMAP-mode in HadGEM3 ICP Report M3 .
- Integrated Climate Programme report (Mar11) describing latest UKCA developments for HadGEM3 UKCA ICP March 2011 .
- Scoping document for HadGEM3 recommends including GLOMAP-mode in UKCA for HadGEM3 HadGEM3-ES Scoping document .
- Coupling of GLOMAP-mode aerosol to UM radiation scheme UKCA RADAER .
- Integrated Climate Programme report (Feb12) UKCA merged code ready to form part of version 8.2 of the Unified Model UKCA ICP Feb12 (merged code) .
Aerosols Cloud Coupling
Aerosol Cloud Coupling: the modal UKCA scheme [Mann et al., 2010] has been coupled by Oxford and the MetOffice to the PC2 cloud scheme [Wilson et al., 2008] via an explicit Köhler theory based activation scheme [Abdul-Razzak & Ghan, 2000].
- Features:
- Sub-grid scale probability density function for updraft velocities coupled to turbulent kinetic energy
- Coupling to cloud radiative properties (i.e. cloud albedo effects)
- Coupling to precipitation formation scheme (i.e. cloud lifetime effects)
- Publications:
- West et al. (in preparation)
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
