Source code for zvalues
################################################################################
'''Module "zvalues", July 2010, is part of
BETR-Research by Harald von Waldow <hvwaldow@chem.ethz.ch>, which is
based on BETR-Global by Matt MacLeod <matthew.macleod@chem.ethz.ch>
This module calculates Z-values'''
################################################################################
from numpy import *
import inspect
from globalz import *
import copy
[docs]class Zvalues():
'''This class constructs a dictionary with compartment-IDs as keys and
dictionaries with bulk- and sub-compartment Z-values (mol/Pa/m^3) as values.
It calls all a method Z<compartment_ID> for each compartment in compdict.
This method has to exist, and must return a dictionary with keys "bulk" and
optionally sub-compartment names.
In case no Z-values are necessary to calculate processes for a particular
compartment with ID <x>, define a function Z<x> that returns an empty
dictionary.'''
## dont't touch this ###########################################################
def __init__(self, par, compdict, chempardict):
self.par=par
self.compdict=compdict
self.chempardict=chempardict
empty=[]
for i in arange(0,len(compdict)):
empty.append({})
self.Z=dict(zip(self.compdict.keys(), empty))
for c in self.compdict.keys():
try:
self.Z[c]=getattr(self,'Z'+str(c))()
except AttributeError:
sys.exit('Calculation of Z-values for compartment {0:d} '
+'not implemented. Aborting !'.format(c))
################################################################################
## DEFINE Z-VALUES FOR NEW COMPARTMENTS HERE ###################################
#
# Functions that calculate Z-values for different compartments
# and sub-compartments. Each function returns a dictionary containing
# the sub-compartment names and/or 'bulk' as keys, and the
# Z-values (mol/Pa/m^3) as values.
[docs] def Z1(self):
'''Z-values for upper air'''
T=self.par[self.compdict[1]['temp_variable']] #temperature field
zdict={}
zdict['air']=(R*T)**-1
# aerosol-air partitioning coefficient
# based on Cousins & Mackay review and 20% by weight octanol in aerosols
Kqa=0.42*self.chempardict[1]['Koa']
zdict['aerosol']=zdict['air']*Kqa
zdict['bulk']=(1-self.par['fp1'])*zdict['air']+\
self.par['fp1']*zdict['aerosol']
return(zdict)
[docs] def Z2(self):
'''Z-values for lower air'''
T=self.par[self.compdict[2]['temp_variable']] #temperature field
zdict={}
zdict['air']=1/(R*T)
# aerosol-air partitioning coefficient
# based on Cousins & Mackay review and 20% by weight octanol in aerosols
Kqa=0.42*self.chempardict[2]['Koa']
zdict['aerosol']=zdict['air']*Kqa
zdict['bulk']=(1-self.par['fp2'])*zdict['air']+\
self.par['fp2']*zdict['aerosol']
## this is a pseudo Z-value that takes into account the
## changed bulk Z-value of the atmosphere during rain events.
### ## volume fraction of water in air during rain
norainmask = self.par['stwet'] == 0
stwet_tmp=copy.copy(self.par['stwet'])
stwet_tmp[norainmask]=1
mtc_event=self.par['precip']\
*(self.par['stdry']+self.par['stwet'])/stwet_tmp
mtc_event[norainmask]=0
fvw=mtc_event/self.par['vrain']
zrain=zdict['air']/self.chempardict[2]['Kaw'] # actual Z-value of rain
zdict['rain']=zrain*zdict['bulk']/(fvw*zrain+(1-fvw)*zdict['bulk'])
return(zdict)
[docs] def Z3(self):
'''Z-values for vegetation'''
T=self.par[self.compdict[3]['temp_variable']] #temperature field
zdict={}
zdict['water']=(R*T*self.chempardict[3]['Kaw'])**-1
# vegetation-flesh - water partitioning coefficient.
# fo3 = volume fraction of pseudo octanol in vegetation-flesh
Kvegw = self.par['fo3']*self.chempardict[3]['Kow']
zdict['flesh']=zdict['water']*Kvegw
zdict['bulk']=self.par['fw3']*zdict['water']+\
(1-self.par['fw3'])*zdict['flesh']
return(zdict)
[docs] def Z4(self):
'''Z-values for freshwater'''
T=self.par[self.compdict[4]['temp_variable']] #temperature field
zdict={}
zdict['water']=(R*T*self.chempardict[4]['Kaw'])**-1
# Kqw: suspended sediment - water partitioning coeffcient
Kqw=0.41*self.chempardict[4]['Kow'] # organic carbon - water [L/kg]
Kqw*=self.par['focp4'] # susp. sediment - water [L/kg]
Kqw*=self.par['rhop45']/1000 # susp. sediment - water [L/L]
zdict['sussed']=zdict['water']*Kqw
# Kfw fish(biota) - water partitioning coefficient
# ATT : reference for '0.05' in Kfw=0.05*Kow ?
Kfw=0.05*self.chempardict[4]['Kow']
zdict['biota']=zdict['water']*Kfw
zdict['bulk']=(1-self.par['fp4']-self.par['ff4'])*zdict['water']+\
self.par['fp4']*zdict['sussed']+\
self.par['ff4']*zdict['biota']
return(zdict)
[docs] def Z5(self):
'''Z-values for ocean water'''
T=self.par[self.compdict[5]['temp_variable']] #temperature field
zdict={}
# ATT : factor 0.8 in Zoceanwater=0.8*Zfreshwater from BETR-VBA. Why ?
zdict['water']=0.8*(R*T*self.chempardict[5]['Kaw'])**-1
# Kqw: suspended sediment - water partitioning coeffcient
Kqw=0.41*self.chempardict[5]['Kow'] # organic carbon - water [L/kg]
Kqw*=self.par['focp5'] # susp. sediment - water [L/kg]
Kqw*=self.par['rhop45']/1000 # susp.sediment - water [L/L]
zdict['sussed']=zdict['water']*Kqw
# Kfw fish(biota) - water partitioning coefficient
# ATT : reference for '0.05' in Kfw=0.05*Kow ?
Kfw=0.05*self.chempardict[5]['Kow']
zdict['biota']=zdict['water']*Kfw
zdict['bulk']=(1-self.par['fp5']-self.par['ff5'])*zdict['water']+\
self.par['fp5']*zdict['sussed']+\
self.par['ff5']*zdict['biota']
return(zdict)
[docs] def Z6(self):
'''Z-values for soil'''
T=self.par[self.compdict[6]['temp_variable']] #temperature field
zdict={}
zdict['air']=1/(R*T)
zdict['water']=zdict['air']/self.chempardict[6]['Kaw']
# Ksw : solids in soil - water partitioning coefficient
Ksw=0.41*self.chempardict[6]['Kow'] # organic carbon - water [L/kg]
Ksw*=self.par['focs6'] # solid fraction - water [L/kg]
Ksw*=self.par['rhos6']/1000 # solid fraction - water [L/L]
zdict['solids']=zdict['water']*Ksw
zdict['bulk']=self.par['fa6']*zdict['air']+\
self.par['fw6']*zdict['water']+\
self.par['fs6']*zdict['solids']
return(zdict)
[docs] def Z7(self):
'''Z-values for sediment'''
T=self.par[self.compdict[7]['temp_variable']] #temperature field
zdict={}
zdict['water']=(R*T*self.chempardict[7]['Kaw'])**-1
# Ksedw : solids in sediment - water partitioning coefficient
Ksedw=0.41*self.chempardict[7]['Kow'] # organic carbon - water [L/kg]
Ksedw*=self.par['focs7'] # solid fraction - water [L/kg]
Ksedw*=self.par['rhos7']/1000 # solid fraction - water [L/L]
zdict['solids']=zdict['water']*Ksedw
zdict['bulk']=self.par['fw7']*zdict['water']+\
self.par['fs7']*zdict['solids']
return(zdict)
###############################################################################
