Difference between revisions of "UKCA & UMUI Tutorial 8"
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'''Note:''' As with the 2D dry deposition values in '''depvel_defs_<span style="color:blue">scheme</span>''', the order of '''henry_defs_<span style="color:blue">scheme</span>''' also assumes that the values are in the same order as the species (that wet deposit) in the '''chch_defs_<span style="color:blue">scheme</span>''' array. |
'''Note:''' As with the 2D dry deposition values in '''depvel_defs_<span style="color:blue">scheme</span>''', the order of '''henry_defs_<span style="color:blue">scheme</span>''' also assumes that the values are in the same order as the species (that wet deposit) in the '''chch_defs_<span style="color:blue">scheme</span>''' array. |
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+ | ===Increase the value of JPDW=== |
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− | ! The following formula is used to calculate the effective Henry's Law coef, |
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+ | |||
− | ! which takes the affects of dissociation and complex formation on a species' |
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+ | Similar to when adding dry deposition of a species you will need to increase the size of the '''JPDW''' counter. This is done with a hand-edit, the value of '''JPDW''' being set in the '''CNTLATM''' file in the <tt>$HOME/umui_jobs/<span style="color:blue">jobid</span></tt> directory. |
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− | ! solubility (see Giannakopoulos, 1998) |
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+ | |||
− | ! |
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+ | ==Task 8.1: Add wet deposition of a species== |
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− | ! H(eff) = K(298)exp{[-deltaH/R]x[(1/T)-(1/298)]} |
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+ | |||
− | ! |
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+ | <span style="color:green">'''Task 8.1:''' Add in wet deposition for '''BOB''', using the following values:</span> |
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− | ! The data in columns 1 and 2 above give the data for this gas-aqueous transfer, |
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+ | |||
− | ! Column 1 = K(298) [M/atm] |
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+ | {| border="1" |
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− | ! Column 2 = -deltaH/R [K-1] |
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+ | ! <math>\ k(298)\ </math> || <math>\ -\left({\Delta H}/R\right)\ </math> || <math>\ k(298)</math> for the 1st dissociatation || <math>\ -\left({\Delta H}/R\right)</math> for the 1st dissociatation || <math>\ k(298)</math> for the 2nd dissociatation || <math>\ -\left({\Delta H}/R\right)</math> for the 2nd dissociatation |
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− | ! |
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+ | |- |
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− | ! If the species dissociates in the aqueous phase the above term is multiplied by |
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+ | | <math>0.13 \times 10^{+05}</math> || <math>0.69 \times 10^{+04}</math> || <math>0.1 \times 10^{-04}</math> || 0.0 || 0.0 || 0.0 |
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− | ! another factor of 1+{K(aq)/[H+]}, where |
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+ | |} |
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− | ! K(aq) = K(298)exp{[-deltaH/R]x[(1/T)-(1/298)]} |
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+ | |||
− | ! The data in columns 3 and 4 give the data for this aqueous-phase dissociation, |
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− | ! Column 3 = K(298) [M] |
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− | ! Column 4 = -deltaH/R [K-1] |
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− | ! The data in columns 5 and 6 give the data for a second dissociation, |
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− | ! e.g for SO2, HSO3^{-}, and SO3^{2-} |
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− | ! Column 5 = K(298) [M] |
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− | ! Column 6 = -deltaH/R [K-1] |
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Revision as of 16:58, 24 June 2013
Adding Wet Deposition
The formulationn used in UKCA is described in Giannakopoulos (1999)[1]. This scheme uses the following formula to calculate the effective Henry's Law coefficient
where is the rate constant at 298K.
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.
Turning on Wet Deposition for a Species
Chemistry Scheme Specification
Within the UKCA code, whether a species is wet 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 7th column turns on wet deposition of that species (being 0 otherwise). You will need to change the 0 to a 1 for the species that you wish to now wet deposit.
Setting Henry's Law values
In the ukca_chem_scheme.F90 the parameters required to calculate are held in the henry_defs_scheme array, and has format
for the 1st dissociatation | for the 1st dissociatation | for the 2nd dissociatation | for the 2nd dissociatation |
Columns 3 and 4 are used if the species dissociates in the aqueous phase. In this case, is futher multiplied by a factor of
where
In this case, columns 3 and 4 contain the values of and used in the above formula. Similarly, if the dissasociates a second time then a further factor of , where is calculated from the values of and in columns 5 and 6.
Note: As with the 2D dry deposition values in depvel_defs_scheme, the order of henry_defs_scheme also assumes that the values are in the same order as the species (that wet deposit) in the chch_defs_scheme array.
Increase the value of JPDW
Similar to when adding dry deposition of a species you will need to increase the size of the JPDW counter. This is done with a hand-edit, the value of JPDW being set in the CNTLATM file in the $HOME/umui_jobs/jobid directory.
Task 8.1: Add wet deposition of a species
Task 8.1: Add in wet deposition for BOB, using the following values:
for the 1st dissociatation | for the 1st dissociatation | for the 2nd dissociatation | for the 2nd dissociatation | ||
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0.0 | 0.0 | 0.0 |
Written by Luke Abraham 2013