Jeffery A. Shook

26 Apr 11

Correlation Between Wind Direction and Observed BrO concentrations

Hypothesis:Wind direction and BrO concentrations

(pptv) are correlated.Objectives:

Using regression fitting, bootstrap method, and correlation coefficient test the hypothesis above.

Objectives and Hypothesis

Data used was collected during the 2010 Greenland field mission using a Chemical Ionization Mass SpectrometerData collected from 26 May 10 to 20 Jun 10. Location: Summit Station Greenland (72°35'46.4"N 38°25'19.1"W)

Data Acquisition

Original Data

0

100

200

300

400

Date(GMT)

Win

d D

irect

ion

(deg

rees

)

05/23 05/30 06/06 06/13 06/20 06/270

10

20

30

40

BrO

mix

ing

ratio

(ppt

)

BrO pptv and Wind Direction (Summit Station Greenland)

Bootstrap Histogram

0.135 0.14 0.145 0.15 0.155 0.16 0.165 0.170

10

20

30

40

50

60

70Histogram of Bootstrap Resampling

Correlation Coefficient 'r'

Boo

tsra

p sa

mpl

es

Regression Fitting

0 50 100 150 200 250 300 350 400-5

0

5

10

15

20

25

30

35

40BrO pptv vs Wind Direction

Wind Direction (degrees)

BrO

mix

ing

ratio

(ppt

v)

BrO pptvLeast Squares FitLeast Squares Error BoundLeast Squares Error BoundReduced Major Axis Fit

BrO concentrations have small correlation due to low correlation coefficient value (0.1539)Bootstrap method confirmed correlation coefficientAverage wind direction: 192 deg. (S)Best correlation regression—Least Squares method.

Conclusions