FATE OF MERCURY IN THE ARCTIC Michael Evan ... - COGCI

Fate of Mercury in the Arctic 102
RGM pg m-3
500
450
run nr. 2, valve stuck open in REA
system
400
350
300
250
200
150
100
50
0
Comparison of total RGM concentrations, Barrow 2001
1130 total
RGM REA total
1 2 3 4 5 6 7 8 9 10 12 11(dark)
REA flux run number
Figure 22 A comparison of RGM air concentrations between the REA system and a co-located TEKRAN model
1130 mercury speciation unit. Due to the different heating mantles, it is expected that the REA
system will have lower RGM values, since the annular denuders were only heated to 50 0 C above
ambient. and did so in all but 2 cases, excluding run nr. 2. The average percent difference between
the two measurements is 24% with a standard deviation of 42, excluding run nr. 2. RGM
measurements from S. Brooks TEKRAN 1130, this author used a linear relationship between time
and concentration for the 2537A since the run start times for the two instruments were different.
The flux was divided by the total concentration to determine the depositional velocity. Table 2.
page 75, has the average values reported in the REA system data output file runname.txt. It is seen
that for the measurement periods, the average temperature was rising, during the campaign, while
wind speed was on average, generally consistent. Wind direction was more variable coming from
the direction of Barrow most of the time, instead of the coast. The standard deviation of the vertical
wind velocity and the value for the proportionality constant, are on average, stable, as should be
expected for the weather conditions.