Difference between revisions of "UKCA & UMUI Tutorial 7"
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UKCA uses two different dry-deposition schemes: |
UKCA uses two different dry-deposition schemes: |
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− | * A simple 2D parameterisation described by Giannakopoulos (1999) [1], Ganzeveld and Lelieveld (1995)[2], and Sander and Crutzen |
+ | * A simple 2D parameterisation described by Giannakopoulos (1999) [1], Ganzeveld and Lelieveld (1995)[2], and Sander and Crutzen (1996)[3]. |
* A more detailed interactive parameterisation, based on the Wesely scheme (Wesely, 1989; Sanderson 2007)[4,5] |
* A more detailed interactive parameterisation, based on the Wesely scheme (Wesely, 1989; Sanderson 2007)[4,5] |
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Revision as of 09:27, 24 June 2013
Adding Dry Deposition
UKCA uses two different dry-deposition schemes:
- A simple 2D parameterisation described by Giannakopoulos (1999) [1], Ganzeveld and Lelieveld (1995)[2], and Sander and Crutzen (1996)[3].
- A more detailed interactive parameterisation, based on the Wesely scheme (Wesely, 1989; Sanderson 2007)[4,5]
The default is to use the 2D scheme, although it is advisable to use the interactive scheme. Within the UKCA code, whether a species is dry deposited or not is controlled in the ukca_chem_scheme.F90 file. In the chch_defs_scheme array there are lines like
chch_t( 10,'HONO2 ', 1,'TR ',' ', 1, 1, 0), & ! 10 DD: 7,WD: 4, chch_t( 11,'H2O2 ', 1,'TR ',' ', 1, 1, 0), & ! 11 DD: 8,WD: 5,
Where the 1 in the 6th column turns on dry-deposition of that species.
References
- Giannakopoulos, C., M. P. Chipperfield, K. S. Law, and J. A. Pyle (1999), Validation and intercomparison of wet and dry deposition schemes using 210Pb in a global three-dimensional off-line chemical transport model, J. Geophys. Res., 104(D19), 23761–23784, doi:10.1029/1999JD900392.
- Ganzeveld, L., and J. Lelieveld (1995), Dry deposition parameterization in a chemistry general circulation model and its influence on the distribution of reactive trace gases, J. Geophys. Res., 100(D10), 20999–21012, doi:10.1029/95JD02266.
- Sander, R., and P. J. Crutzen (1996), Model study indicating halogen activation and ozone destruction in polluted air masses transported to the sea, J. Geophys. Res., 101(D4), 9121–9138, doi:10.1029/95JD03793.
- M.L. Wesely, Parameterization of surface resistances to gaseous dry deposition in regional-scale numerical models, Atmospheric Environment (1967), Volume 23, Issue 6, 1989, Pages 1293-1304, ISSN 0004-6981, http://dx.doi.org/10.1016/0004-6981(89)90153-4.
- Sanderson, M. G., Collins, W. J., Hemming, D. L. and Betts, R. A. (2007), Stomatal conductance changes due to increasing carbon dioxide levels: Projected impact on surface ozone levels. Tellus B, 59: 404–411. doi: 10.1111/j.1600-0889.2007.00277.x
2D Dry Deposition Scheme
The deposition velocities for the 2D scheme are defined in the depvel_defs_scheme array, which is held in the ukca_chem_scheme.F90 module. This is a large array made up of size (6,5) blocks. These blocks mean
Summer (day) velocity over water | Summer (night) velocity over water | Summer (24h ave.) velocity over water | Winter (day) velocity over water | Winter (night) velocity over water | Winter (24h ave.) velocity over water |
Summer (day) velocity over forest | Summer (night) velocity over forest | Summer (24h ave.) velocity over forest | Winter (day) velocity over forest | Winter (night) velocity over forest | Winter (24h ave.) velocity over forest |
Summer (day) velocity over grass | Summer (night) velocity over grass | Summer (24h ave.) velocity over grass | Winter (day) velocity over grass | Winter (night) velocity over grass | Winter (24h ave.) velocity over grass |
Summer (day) velocity over desert | Summer (night) velocity over desert | Summer (24h ave.) velocity over desert | Winter (day) velocity over desert | Winter (night) velocity over desert | Winter (24h ave.) velocity over desert |
Summer (day) velocity over ice | Summer (night) velocity over ice | Summer (24h ave.) velocity over ice | Winter (day) velocity over ice | Winter (night) velocity over ice | Winter (24h ave.) velocity over ice |
and are in cm/s. The desert category is not used, and only the day and night values are taken. Examples of these values are
! 1 O3 (Ganzeveld & Lelieveld (1995) note 1 (modified to same as Guang) 0.05, 0.05, 0.05, 0.05, 0.05, 0.05, & ! 1.1 0.85, 0.30, 0.65, 0.65, 0.25, 0.45, & ! 1.2 0.65, 0.25, 0.45, 0.65, 0.25, 0.45, & ! 1.3 0.18, 0.18, 0.18, 0.18, 0.18, 0.18, & ! 1.4 0.05, 0.05, 0.05, 0.05, 0.05, 0.05, & ! 1.5 ! 2 NO (inferred from NO2 - see Giannakopoulos (1998)) 0.00, 0.00, 0.00, 0.00, 0.00, 0.00, & ! 2.1 0.14, 0.01, 0.07, 0.01, 0.01, 0.01, & ! 2.2 0.10, 0.01, 0.06, 0.01, 0.01, 0.01, & ! 2.3 0.01, 0.01, 0.01, 0.01, 0.01, 0.01, & ! 2.4 0.00, 0.00, 0.00, 0.00, 0.00, 0.00, & ! 2.5
Note: When adding new deposition you should be careful. UKCA assumes that the order of this array is the same as the order of the species in the chch_defs_scheme array. If you are adding a value for a species in the middle of the list then you will need to slot it in to the appropriate place in the exiting depvel_defs_scheme array (and change the size of this array accordingly).
This scheme is controlled in ukca_ddeprt.F90.
Written by Luke Abraham 2013