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:
   
* A simple 2D parameterisation described by Giannakopoulos (1999) [1], Ganzeveld and Lelieveld (1995)[2], and Sander and Crutzen 1996 (JGR 101 9121)[3].
+
* 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]
   

Revision as of 09:27, 24 June 2013

Back to UKCA & UMUI Tutorials

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

  1. 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.
  2. 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.
  3. 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.
  4. 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.
  5. 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