Geoscience Reference
In-Depth Information
To simplify the calculation scheme presented in the diagram in Fig. 1.35 ,
advective processes in the equations of the MGBN item can be described by a
superposition of the
uxes H 14 and H 15 . The computer realization of the equations of
the MGBN item introduces into the equations of the MGBN item some corrections
for the agreement between the dimensionalities of the variables in conformity with
the spatial digitization of
fl
uxes H i given below for
their consideration in the MGBN should be corrected following this criterion.
Different versions of the MGBN unit of the BCSS model can be synthesized
depending on the parameterization of
Ξ
. Therefore the estimates of the
fl
uxes H i . Krapivin and Varotsos (2008) the
fl
ux H 16 of nitrogen
fl
fixed in the atmosphere over any ocean basin described by the
relationship:
H 16 ¼½ k 1 ðh 1 Þ D T
þ k 2 R W N A ;
ʔ
ʸ 1 is the indicator of the tem-
where
T is the atmospheric temperature variation,
perature dependence of the rate of atmospheric
fixation of nitrogen, R W is precip-
itation, ʻ 1 and ʻ 2 are the coefficients.
The equation of atmospheric
fixation over a land site
Ξ ij is written by analogy to
H 16 :
H 8 ; ij ¼½ k 3 ðh 1 Þ D T
þ k 4 R W ; ij N A ;
where
ʻ 3 and
ʻ 4 are coef
cients.
To estimate the coef
cients
ʻ i (i =1,
, 4), as a
first approximation one can
fluxes and precipitation. If we assume H 16 ¼
use average data on nitrogen
fl
027 t km 2 year 1 , estimate local precipita-
tion over the ocean and land at 1.01 and 0.24 m year 1 , respectively, and the
convective precipitation over the ocean and land at 0.19 and 0.116 m year 1 ,
respectively, we obtain
96 10 3 tkm 2 year 1
9
:
;
H 8 ¼ 0
:
ʻ 1 = 0.00498,
ʻ 2 = 0.00458,
ʻ 3 = 0.0135, and
ʻ 4 = 0.0285.
These estimates are easily speci
ed with account of local data at a
fixed time
moment for smaller regions and water bodies.
The
flux of nitrogen H 1 is determined by the geothermal activity of the Earth. Its
estimates testify to a necessity of consideration of this constituent in the global
model. In particular, for instance, in the nitrogen fumaroles of Vesuvius the content
of nitrogen by weight constitutes 98 %, in gases of the lavas of the Hawaiian
volcanoes there are only 5.7 % of nitrogen, and over the globe an input of juvenile
nitrogen averages 0.4
fl
10 6 t year 1 . Let H 1 be a function of time approximating a
statistical series of observations. A more strict account of this
×
flux of nitrogen in the
model can be realized by using the algorithms of parameterization of random
processes, for instance, with the use of the evolutionary modeling. However, within
the global model, orientated toward describing the processes in time steps of
decades, it is enough to use average annual data.
fl
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