Eight-Site SA Speciation Trends Final Report September 24, 2003

APPENDIX G:

GRAPHICAL REPRESENTATION OF THE

SOURCE APPORTIONMENT RESULTS FOR

HOUSTON, TEXAS

Eight-Site SA Speciation Trends Final Report G-1 September 24, 2003

Appendix G: Graphical Representation of the

Source Apportionment Results for Houston, Texas

This appendix shows a series of nine plots for each source indicated by the PMF model

for Houston, Texas. These plots are used to help identify the sources by understanding some of

the characteristics of the sources. The plots included for each source are:

1. The source profile plot.

2. The time series of the source strength.

3. Bar charts of the source strength for various categories.

4. The source pollution rose.

5. The source region(s) as indicated by the source contribution function.

6. The source region(s) as indicated by the incremental probability function.

7. Back trajectories color coded by source strength.

8. Scatter plots of the source strength versus ambient temperature for each season

and scatter plots of the source strength versus ambient pressure.

The profile plot shows the relative composition of the source (bars with the scale on the

left) and the percent of the total species mass observed at the receptor attributed to the source

(line with the scale on the right). The relative chemical composition is the main basis for the

source identifications. Generally, the other plots are used to refine or confirm the identification

made from this first plot.

The time series plot shows the source strength as a function of time. Two scales are

shown. On the left is the source strength LQ JP

3

and on the right is the relative source strength,

which is the daily source strength divided by the mean source strength. The latter is the direct

output from the PMF model and can be used to compare events among sources.

The bar charts show the mean source strength when stratified by wind speed (including

calm periods), weekday/weekend, and season (winter is December, January, and February).

Each of these plots provides supplemental information for identifying the source.

The pollution rose shows the mean source strength by wind sector and wind speed

category. These plots can indicate the source location for local sources. Winds less than 1 mph

are not used in generating this plot, since the wind direction is not always clear for low winds.

These periods are indicated in the bar charts.

The next two plots are the source regions as indicated by either the source contribution

function (the probability of a high source day given that the back trajectory passes over the grid

point) or the incremental probability function (the probability that source strength is high and the

back trajectory passes over the grid point minus the probability that the back trajectory passes

over the grid point). High and low days are defined as above. To minimize the effects of having

too few trajectories within a grid cell, the plots for the source contribution function are of a lower

bound for a 90 percent confidence interval for the probability of a high day. Hence, only the
Eight-Site SA Speciation Trends Final Report G-2 September 24, 2003

areas that have a probability that is significantly above 20 percent are plotted. For the

incremental probability plot, this same effect is avoided by dividing the incremental probability

by its standard error and plotting the regions that are at least 1 standard error away from zero (in

either direction). These modifications to the usual source contribution function and the

incremental probability make it easier to compare the plots and the numerical values among

different sources.

The back trajectory plots are color coded by source strength. The low source strength

days are blue and represent the lowest 20 percent of the source strengths. The high source days

are red and represent the highest 20 percent of the source strengths. The remainder of the back

trajectories are plotted in green. These can give some indication of source region, but are usually

too messy for that purpose. The main use for these plots is as noted above; they show when the

effects of high pressure systems play a significant role in the source strength.

The first set of scatter plots shows any relationship between ambient temperature and the

source strength. The plots are separated by season to keep extreme observations from

dominating the relationship. Underneath these plots is a scatter plot that shows any relationship

between local ambient pressure and the source strength. Very few sources show a relationship

since source activity is rarely related to pressure. The source strength are more often modulated

by the concentrating effects of high pressure systems located tangent to the site. These should be

compared to the back trajectories for high source days (the previous plot). The back trajectories

around high pressure systems will be clockwise ending at the receptor. Generally, the other

source strength plots, in particular the remaining back trajectory source region plots, need to be

discounted for this effect when it is present.
Eight-Site SA Speciation Trends Final Report G-3 September 24, 2003

Figure G-1. Profile Plot (Top), Time Series Plot (Middle), and Bar Charts of the Source

Strength Averaged by Wind Speed, Day of Week, and Season (Bottom) for

Houston, Texas, Source 1 - Crustal.
Eight-Site SA Speciation Trends Final Report G-4 September 24, 2003

Figure G-2. Pollution Rose for Houston, Texas, Source 1 - Crustal.

Figure G-3 Source Contribution Contour Plot for Houston, Texas, Source 1 - Crustal.
Eight-Site SA Speciation Trends Final Report G-5 September 24, 2003

Figure G-4 Incremental Probability Contour Plot for Houston, Texas, Source 1 -

Crustal.

Figure G-5 Back Trajectories Color Coded by Source Strength Category for

Houston, Texas, Source 1 - Crustal.
Eight-Site SA Speciation Trends Final Report G-6 September 24, 2003

Figure G-6 Scatter Plot of Source Strength Versus Mean Daily Temperature (Rows 1

and 2) and Pressure (bottom) for Houston, Texas, Source 1 - Crustal.
Eight-Site SA Speciation Trends Final Report G-7 September 24, 2003

Figure G-7. Profile Plot (Top), Time Series Plot (Middle), and Bar Charts of the Source

Strength Averaged by Wind Speed, Day of Week, and Season (Bottom) for

Houston, Texas, Source 2 - Vegetative Burning and Fireworks.
Eight-Site SA Speciation Trends Final Report G-8 September 24, 2003

Figure G-8 Pollution Rose for Houston, Texas, Source 2 - Vegetative Burning and

Fireworks.

Figure G-9 Source Contribution Contour Plot for Houston, Texas, Source 2 -

Vegetative Burning and Fireworks.
Eight-Site SA Speciation Trends Final Report G-9 September 24, 2003

Figure G-10 Incremental Probability Contour Plot for Houston, Texas, Source 2 -

Vegetative Burning and Fireworks.

Figure G-11 Back Trajectories Color Coded by Source Strength Category for

Houston, Texas, Source 2 - Vegetative Burning and Fireworks.
Eight-Site SA Speciation Trends Final Report G-10 September 24, 2003

Figure G-12 Scatter Plot of Source Strength Versus Mean Daily Temperature (Rows 1

and 2) and Pressure (bottom) for Houston, Texas, Source 2 - Vegetative

Burning and Fireworks.
Eight-Site SA Speciation Trends Final Report G-11 September 24, 2003

Figure G-13 Profile Plot (Top), Time Series Plot (Middle), and Bar Charts of the Source

Strength Averaged by Wind Speed, Day of Week, and Season (Bottom) for

Houston, Texas, Source 3 - Industrial.
Eight-Site SA Speciation Trends Final Report G-12 September 24, 2003

Figure G-14 Pollution Rose for Houston, Texas, Source 3 - Industrial.

Figure G-15 Source Contribution Contour Plot for Houston, Texas, Source 3 -Industrial.
Eight-Site SA Speciation Trends Final Report G-13 September 24, 2003

Figure G-16 Incremental Probability Contour Plot for Houston, Texas, Source 3 -

Industrial.

Figure G-17 Back Trajectories Color Coded by Source Strength Category for

Houston, Texas, Source 3 - Industrial.
Eight-Site SA Speciation Trends Final Report G-14 September 24, 2003

Figure G-18 Scatter Plot of Source Strength Versus Mean Daily Temperature (Rows 1

and 2) and Pressure (bottom) for Houston, Texas, Source 3 - Industrial.
Eight-Site SA Speciation Trends Final Report G-15 September 24, 2003

Figure G-19 Profile Plot (Top), Time Series Plot (Middle), and Bar Charts of the Source

Strength Averaged by Wind Speed, Day of Week, and Season (Bottom) for

Houston, Texas, Source 4 - Mobile Sources.
Eight-Site SA Speciation Trends Final Report G-16 September 24, 2003

Figure G-20 Pollution Rose for Houston, Texas, Source 4 - Mobile Sources.

Figure G-21 Source Contribution Contour Plot for Houston, Texas, Source 4 - Mobile

Sources.
Eight-Site SA Speciation Trends Final Report G-17 September 24, 2003

Figure G-22 Incremental Probability Contour Plot for Houston, Texas, Source 4 - Mobile

Sources.

Figure G-23 Back Trajectories Color Coded by Source Strength Category for

Houston, Texas, Source 4 - Mobile Sources.
Eight-Site SA Speciation Trends Final Report G-18 September 24, 2003

Figure G-24 Scatter Plot of Source Strength Versus Mean Daily Temperature (Rows 1

and 2) and Pressure (bottom) for Houston, Texas, Source 4 - Mobile

Sources.
Eight-Site SA Speciation Trends Final Report G-19 September 24, 2003

Figure G-25 Profile Plot (Top), Time Series Plot (Middle), and Bar Charts of the Source

Strength Averaged by Wind Speed, Day of Week, and Season (Bottom) for

Houston, Texas, Source 5 - Marine Ammonium Nitrate.
Eight-Site SA Speciation Trends Final Report G-20 September 24, 2003

Figure G-26 Pollution Rose for Houston, Texas, Source 5 - Marine Ammonium Nitrate.

Figure G-27 Source Contribution Contour Plot for Houston, Texas, Source 5 - Marine

Ammonium Nitrate.
Eight-Site SA Speciation Trends Final Report G-21 September 24, 2003

Figure G-28 Incremental Probability Contour Plot for Houston, Texas, Source 5 - Marine

Ammonium Nitrate.

Figure G-29 Back Trajectories Color Coded by Source Strength Category for

Houston, Texas, Source 5 - Marine Ammonium Nitrate.
Eight-Site SA Speciation Trends Final Report G-22 September 24, 2003

Figure G-30 Scatter Plot of Source Strength Versus Mean Daily Temperature (Rows 1

and 2) and Pressure (bottom) for Houston, Texas, Source 5 - Marine

Ammonium Nitrate.
Eight-Site SA Speciation Trends Final Report G-23 September 24, 2003

Figure G-31 Profile Plot (Top), Time Series Plot (Middle), and Bar Charts of the Source

Strength Averaged by Wind Speed, Day of Week, and Season (Bottom) for

Houston, Texas, Source 6 - Mobile Mn Source or Grain Dust.
Eight-Site SA Speciation Trends Final Report G-24 September 24, 2003

Figure G-32 Pollution Rose for Houston, Texas, Source 6 - Mobile Mn Source or Grain

Dust.

Figure G-33 Source Contribution Contour Plot for Houston, Texas, Source 6 - Mobile Mn

Source or Grain Dust.
Eight-Site SA Speciation Trends Final Report G-25 September 24, 2003

Figure G-34 Incremental Probability Contour Plot for Houston, Texas, Source 6 - Mobile

Mn Source or Grain Dust.

Figure G-35 Back Trajectories Color Coded by Source Strength Category for

Houston, Texas, Source 6 - Mobile Mn Source or Grain Dust.
Eight-Site SA Speciation Trends Final Report G-26 September 24, 2003

Figure G-36 Scatter Plot of Source Strength Versus Mean Daily Temperature (Rows 1

and 2) and Pressure (bottom) for Houston, Texas, Source 6 - Mobile Mn

Source or Grain Dust.
Eight-Site SA Speciation Trends Final Report G-27 September 24, 2003

Figure G-37 Profile Plot (Top), Time Series Plot (Middle), and Bar Charts of the Source

Strength Averaged by Wind Speed, Day of Week, and Season (Bottom) for

Houston, Texas, Source 7 - Coal Combustion (Ni).
Eight-Site SA Speciation Trends Final Report G-28 September 24, 2003

Figure G-38 Pollution Rose for Houston, Texas, Source 7 - Coal Combustion (Ni).

Figure G-39 Source Contribution Contour Plot for Houston, Texas, Source 7 - Coal

Combustion (Ni).
Eight-Site SA Speciation Trends Final Report G-29 September 24, 2003

Figure G-40 Incremental Probability Contour Plot for Houston, Texas, Source 7 - Coal

Combustion (Ni).

Figure G-41 Back Trajectories Color Coded by Source Strength Category for

Houston, Texas, Source 7 - Coal Combustion (Ni).
Eight-Site SA Speciation Trends Final Report G-30 September 24, 2003

Figure G-42 Scatter Plot of Source Strength Versus Mean Daily Temperature (Rows 1

and 2) and Pressure (bottom) for Houston, Texas, Source 7 - Coal

Combustion (Ni).