The composition, seasonal variation and potential sources of the atmospheric wet sulfur (S) and nitrogen (N) _method

Methods

No linear relationship was found between NO2 tropospheric column and no3-, but both well simulated by Y=y0+a*sin (b*x+c ) +e*x indicating NO2 tropospheric column could reflect the trend of no3-but is difficult to quantify no3-.

Data

(1) User defined Function:y=y0+a*sin (b*x+c) +e*x in SigmaPlot

First, generate scatter

Second, define the function "Y=y0+a*sin (b*x+c) +e*x"

equation:

pi=3.14159265358979

f = Y0+a*sin (2*pi*x/b+c)

Fit F to Y

' Fit f to y with weight reciprocal_y

' Fit f to y with weight reciprocal_ysquare

' Fit f to y with weight reciprocal_pred

' Fit f to y with weight reciprocal_predsqr

vavriables:

x = col (1) ' {{prevmin:0.000000}} {{prevmax:5.000000}} {{intervals:100}}

y = col (2)

Reciprocal_y = 1/abs (y)

Reciprocal_ysquare = 1/y^2

reciprocal_pred = 1/abs (f)

RECIPROCAL_PREDSQR = 1/f^2

' Automatic Initial Parameter Estimate Functions

F (q) = SINP (x, y)

Initial Parameters:

A = F (0) [1] ' Auto {{previous:95}}

b = if (f (0) [2]<>0, F (0) [2], 1) ' Auto {{previous:1.8}}

c = F (0) [3] ' Auto {{previous:. 5}}

Y0 = mean (y) ' Auto {{previous:5}}

Constraits

A>0

B>0

c>-6.28

c<6.28

Third, gernrate the curve

Additional Procedure:

Multiple lines:

Linear trend, then, right click, Curve fit, Line/scatter

(2) made "Y=y0+a*sin (b*x+c) +e*x" in Matlab

Cftool-v1

The composition, seasonal variation and potential sources of the atmospheric wet sulfur (S) and nitrogen (N) _method