Figure 1.
Location of the eigth air monitoring stations deployed in Salvador-BA.
Figure 1.
Location of the eigth air monitoring stations deployed in Salvador-BA.
Figure 2.
Unified distance matrix (U-matrix) and component planes of all analyzed variables (SO2, CO, O3, PM10, NO, NO2, WS, TEMP, RH, and STWD) from the Itaigara station.
Figure 2.
Unified distance matrix (U-matrix) and component planes of all analyzed variables (SO2, CO, O3, PM10, NO, NO2, WS, TEMP, RH, and STWD) from the Itaigara station.
Figure 3.
Hierarchical analysis of the neurons clusters using the Ward linkage method and Euclidean distance for the Itaigara station.
Figure 3.
Hierarchical analysis of the neurons clusters using the Ward linkage method and Euclidean distance for the Itaigara station.
Figure 4.
SOM neurons grouped into four clusters obtained by the hierarchical analysis of the Itaigara station.
Figure 4.
SOM neurons grouped into four clusters obtained by the hierarchical analysis of the Itaigara station.
Figure 5.
Parameter correlation using Ward criterion and distance , where r is Pearson coefficient, for the Itaigara station.
Figure 5.
Parameter correlation using Ward criterion and distance , where r is Pearson coefficient, for the Itaigara station.
Figure 6.
Unified distance matrix (U-matrix) and component planes of all analyzed variables (SO2, CO, O3, PM10, NO, NO2, WS, TEMP, RH and STWD) from the Barros Reis station.
Figure 6.
Unified distance matrix (U-matrix) and component planes of all analyzed variables (SO2, CO, O3, PM10, NO, NO2, WS, TEMP, RH and STWD) from the Barros Reis station.
Figure 7.
Hierarchical analysis of the neurons clusters using the Ward linkage method and Euclidean distance for the Barros Reis station.
Figure 7.
Hierarchical analysis of the neurons clusters using the Ward linkage method and Euclidean distance for the Barros Reis station.
Figure 8.
SOM neurons grouped into three clusters obtained by the hierarchical analysis of the Barros Reis station.
Figure 8.
SOM neurons grouped into three clusters obtained by the hierarchical analysis of the Barros Reis station.
Figure 9.
Parameter correlation using Ward criterion and distance , where r is Pearson coefficient, for the Barros Reis station.
Figure 9.
Parameter correlation using Ward criterion and distance , where r is Pearson coefficient, for the Barros Reis station.
Figure 10.
Unified distance matrix (U-matrix) and component planes of all analyzed variables (SO2, CO, O3, PM10, NO, NO2, WS, TEMP, RH and STWD) from the Campo Grande station.
Figure 10.
Unified distance matrix (U-matrix) and component planes of all analyzed variables (SO2, CO, O3, PM10, NO, NO2, WS, TEMP, RH and STWD) from the Campo Grande station.
Figure 11.
Hierarchical analysis of the neurons clusters using the Ward linkage method and Euclidean distance for the Campo Grande station.
Figure 11.
Hierarchical analysis of the neurons clusters using the Ward linkage method and Euclidean distance for the Campo Grande station.
Figure 12.
SOM neurons grouped into five clusters obtained by the hierarchical analysis of the Campo Grande station.
Figure 12.
SOM neurons grouped into five clusters obtained by the hierarchical analysis of the Campo Grande station.
Figure 13.
Parameter correlation using Ward criterion and distance , where r is Pearson coefficient, for the Campo Grande station.
Figure 13.
Parameter correlation using Ward criterion and distance , where r is Pearson coefficient, for the Campo Grande station.
Figure 14.
Unified distance matrix (U-matrix) and component planes of all analyzed variables (SO2, CO, O3, PM10, NO, NO2, WS, TEMP, RH and STWD) from the Dique do Tororó station.
Figure 14.
Unified distance matrix (U-matrix) and component planes of all analyzed variables (SO2, CO, O3, PM10, NO, NO2, WS, TEMP, RH and STWD) from the Dique do Tororó station.
Figure 15.
Hierarchical analysis of the neurons clusters using the Ward linkage method and Euclidean distance for the Dique do Tororó station.
Figure 15.
Hierarchical analysis of the neurons clusters using the Ward linkage method and Euclidean distance for the Dique do Tororó station.
Figure 16.
SOM neurons grouped into three clusters obtained by the hierarchical analysis of the Dique do Tororó station.
Figure 16.
SOM neurons grouped into three clusters obtained by the hierarchical analysis of the Dique do Tororó station.
Figure 17.
Parameter correlation using Ward criterion and distance , where r is Pearson coefficient, for the Dique do Tororó station.
Figure 17.
Parameter correlation using Ward criterion and distance , where r is Pearson coefficient, for the Dique do Tororó station.
Table 1.
The operation period for each monitoring station provided by CETREL S. A., and the number of data samples available in the dataset before and after the preprocessing step.
Table 1.
The operation period for each monitoring station provided by CETREL S. A., and the number of data samples available in the dataset before and after the preprocessing step.
Station | Operation Start Date | Operation End Date | Number of Rregistered Samples | Number of Samples after Preprocessing |
---|
Barros Reis (BR) | 8 November 2013 | 31 December 2016 | | |
Campo Grande (CG) | 2 July 2011 | 31 December 2016 | | |
Dique do Tororó (DT) | 19 June 2011 | 31 December 2016 | | |
Itaigara (IT) | 18 October 2013 | 30 April 2016 | | |
Table 2.
Descriptive statistics of pollutants and atmospheric data from the Barros Reis station (P = 21,559 samples).
Table 2.
Descriptive statistics of pollutants and atmospheric data from the Barros Reis station (P = 21,559 samples).
Parameters | Magniture | Maximum | Mean | Average | Standard Deviation | Variation Coefficient |
---|
SO2 | ppb | 3.20 | 0.30 | 0.45 | 0.51 | 112.94% |
CO | ppb | 2180.00 | 570.00 | 601.60 | 335.70 | 55.80% |
O3 | ppb | 22.70 | 4.80 | 5.47 | 3.80 | 69.36% |
PM10 | | 129.80 | 37.30 | 40.10 | 19.88 | 49.58% |
NO | ppb | 206.40 | 44.40 | 52.47 | 38.01 | 72.50% |
NO2 | ppb | 49.20 | 13.30 | 14.15 | 7.61 | 53.84% |
WS | m/s | 10.80 | 2.20 | 2.62 | 1.75 | 67.00% |
TEMP | °C | 32.50 | 25.50 | 25.63 | 2.18 | 8.54% |
RH | % | 91.00 | 69.00 | 68.60 | 9.31 | 13.57% |
STWD | ° | 73.30 | 31.30 | 31.61 | 11.61 | 36.73% |
Table 3.
Descriptive statistics of pollutants and atmospheric data from the Campo Grande station (P = 24,559 samples).
Table 3.
Descriptive statistics of pollutants and atmospheric data from the Campo Grande station (P = 24,559 samples).
Parameters | Magniture | Maximum | Mean | Average | Standard Deviation | Variation Coefficient |
---|
SO2 | ppb | 1.70 | 0.20 | 0.32 | 0.31 | 97.20% |
CO | ppb | 1830.00 | 360.00 | 396.60 | 292.70 | 73.81% |
O3 | ppb | 25.00 | 5.20 | 6.01 | 4.18 | 69.5% |
PM10 | | 77.30 | 19.30 | 21.10 | 12.53 | 59.38% |
NO | ppb | 139.00 | 25.10 | 28.03 | 23.37 | 83.38% |
NO2 | ppb | 44.00 | 13.30 | 13.37 | 6.42 | 48.00% |
WS | m/s | 5.10 | 1.20 | 1.42 | 0.93 | 66.01% |
TEMP | °C | 34.30 | 26.50 | 26.72 | 2.31 | 8.66% |
RH | % | 94.00 | 72.00 | 71.12 | 9.54 | 13.41% |
STWD | ° | 79.60 | 53.20 | 52.01 | 13.31 | 25.57% |
Table 4.
Descriptive statistics of pollutants and atmospheric data from the Dique do Tororó station (P = 42,037 samples).
Table 4.
Descriptive statistics of pollutants and atmospheric data from the Dique do Tororó station (P = 42,037 samples).
Parameters | Magniture | Maximum | Mean | Average | Standard Deviation | Variation Coefficient |
---|
SO2 | ppb | 2.00 | 0.20 | 0.33 | 0.40 | 123.15% |
CO | ppb | 1000.00 | 220.00 | 239.40 | 163.90 | 68.44% |
O3 | ppb | 34.30 | 7.20 | 8.15 | 5.37 | 65.88% |
PM10 | | 75.60 | 20.00 | 22.13 | 12.42 | 56.12% |
NO | ppb | 73.60 | 12.40 | 13.77 | 11.54 | 83.78% |
NO2 | ppb | 31.30 | 8.20 | 8.67 | 5.02 | 57.92% |
WS | m/s | 6.90 | 1.50 | 1.63 | 1.01 | 61.72% |
TEMP | °C | 33.90 | 26.30 | 26.46 | 2.31 | 8.75% |
RH | % | 94.00 | 73.00 | 72.46 | 9.10 | 12.56% |
STWD | ° | 78.80 | 33.00 | 38.45 | 15.34 | 39.90% |
Table 5.
Descriptive statistics of pollutants and atmospheric data from the Itaigara station (P = 15,535 samples).
Table 5.
Descriptive statistics of pollutants and atmospheric data from the Itaigara station (P = 15,535 samples).
Parameters | Magniture | Maximum | Mean | Average | Standard Deviation | Variation Coefficient |
---|
SO2 | ppb | 1.60 | 0.10 | 0.2502 | 0.33 | 131.89% |
CO | ppb | 1210.00 | 190.00 | 226.48 | 207.26 | 91.51% |
O3 | ppb | 27.50 | 7.90 | 8.47 | 4.32 | 51.00% |
PM10 | | 67.40 | 13.60 | 16.16 | 10.98 | 67.94% |
NO | ppb | 70.70 | 11.40 | 15.50 | 13.45 | 86.77% |
NO2 | ppb | 31.10 | 7.30 | 8.21 | 5.15 | 62.72% |
WS | m/s | 10.20 | 2.70 | 2.76 | 1.58 | 57.24% |
TEMP | °C | 33.40 | 25.00 | 25.04 | 2.27 | 9.06% |
RH | % | 93.00 | 71.00 | 71.43 | 9.08 | 12.71% |
STWD | ° | 51.30 | 22.80 | 24.32 | 8.13 | 33.42% |
Table 6.
SOM quality measures for Barros Reis Station data (best values in bold).
Table 6.
SOM quality measures for Barros Reis Station data (best values in bold).
| M | z-Score | Min-Max | Logarithmic |
---|
QE | TE | QE | TE | QE | TE |
| 648 | 1.4032 | 0.0649 | 0.2290 | 0.0636 | 0.7173 | 0.0606 |
| 676 | 1.3898 | 0.0687 | 0.2273 | 0.0661 | 0.7108 | 0.0616 |
| 696 | 1.3887 | 0.0668 | 0.2270 | 0.0668 | 0.7096 | 0.0607 |
| 713 | 1.3805 | 0.0631 | 0.2259 | 0.0607 | 0.7051 | 0.0593 |
| 729 | 1.3803 | 0.0612 | 0.2245 | 0.0653 | 0.7032 | 0.0629 |
| 750 | 1.3766 | 0.0660 | 0.2250 | 0.0667 | 0.7017 | 0.0616 |
| 768 | 1.3684 | 0.0649 | 0.2232 | 0.0622 | 0.6977 | 0.0601 |
| 782 | 1.3652 | 0.0701 | 0.2229 | 0.0644 | 0.6950 | 0.0644 |
| 792 | 1.3609 | 0.0655 | 0.2224 | 0.0673 | 0.6957 | 0.0587 |
| 806 | 1.3597 | 0.0658 | 0.2219 | 0.0663 | 0.6948 | 0.0622 |
Table 7.
SOM quality measures for Campo Grande Station data (best values in bold).
Table 7.
SOM quality measures for Campo Grande Station data (best values in bold).
| M | z-Score | Min-Max | Logarithmic |
---|
QE | TE | QE | TE | QE | TE |
| 713 | 1.4216 | 0.0666 | 0.2384 | 0.0626 | 0.7346 | 0.0625 |
| 729 | 1.4187 | 0.0660 | 0.2382 | 0.0667 | 0.7294 | 0.0584 |
| 750 | 1.4131 | 0.0650 | 0.2369 | 0.0664 | 0.7277 | 0.0626 |
| 768 | 1.4082 | 0.0648 | 0.2360 | 0.0640 | 0.7253 | 0.0630 |
| 784 | 1.4099 | 0.0619 | 0.2352 | 0.0685 | 0.7230 | 0.0610 |
| 806 | 1.3994 | 0.0645 | 0.2341 | 0.0670 | 0.7215 | 0.0589 |
| 816 | 1.3948 | 0.0642 | 0.2340 | 0.0624 | 0.7193 | 0.0592 |
| 825 | 1.3949 | 0.0636 | 0.2334 | 0.0636 | 0.7173 | 0.0593 |
| 840 | 1.3925 | 0.0651 | 0.2336 | 0.0669 | 0.7163 | 0.0630 |
| 864 | 1.3898 | 0.0619 | 0.2324 | 0.0643 | 0.7146 | 0.0594 |
Table 8.
SOM quality measures for Dique do Tororó Station data (best values in bold).
Table 8.
SOM quality measures for Dique do Tororó Station data (best values in bold).
| M | z-Score | Min-Max | Logarithmic |
---|
QE | TE | QE | TE | QE | TE |
| 950 | 1.2812 | 0.0686 | 0.2175 | 0.0668 | 0.6834 | 0.0630 |
| 962 | 1.2773 | 0.0684 | 0.2172 | 0.0670 | 0.6814 | 0.0641 |
| 988 | 1.2742 | 0.0668 | 0.2163 | 0.0679 | 0.6802 | 0.0621 |
| 1008 | 1.2687 | 0.0733 | 0.2157 | 0.0676 | 0.6798 | 0.0619 |
| 1024 | 1.2667 | 0.0736 | 0.2152 | 0.0679 | 0.6777 | 0.0659 |
| 1053 | 1.2628 | 0.0702 | 0.2146 | 0.0678 | 0.6745 | 0.0644 |
| 1040 | 1.2639 | 0.0695 | 0.2152 | 0.0688 | 0.6750 | 0.0611 |
| 1064 | 1.2581 | 0.0721 | 0.2141 | 0.0680 | 0.6747 | 0.0660 |
| 1073 | 1.2600 | 0.0706 | 0.2136 | 0.0728 | 0.6718 | 0.0632 |
| 1080 | 1.2609 | 0.0657 | 0.2136 | 0.0717 | 0.6730 | 0.0633 |
Table 9.
SOM quality measures for Itaigara Station data (best values in bold).
Table 9.
SOM quality measures for Itaigara Station data (best values in bold).
| M | z-Score | Min-Max | Logarithmic |
---|
QE | TE | QE | TE | QE | TE |
| 552 | 1.4306 | 0.0584 | 0.2428 | 0.0591 | 0.7736 | 0.0510 |
| 572 | 1.4237 | 0.0603 | 0.2422 | 0.0566 | 0.7709 | 0.0485 |
| 576 | 1.4210 | 0.0618 | 0.2421 | 0.0557 | 0.7704 | 0.0503 |
| 594 | 1.4192 | 0.0548 | 0.2403 | 0.0589 | 0.7684 | 0.0547 |
| 600 | 1.4152 | 0.0593 | 0.2412 | 0.0565 | 0.7659 | 0.0477 |
| 621 | 1.4126 | 0.0574 | 0.2400 | 0.0585 | 0.7654 | 0.0444 |
| 625 | 1.4063 | 0.0573 | 0.2399 | 0.0553 | 0.7625 | 0.0458 |
| 648 | 1.4086 | 0.0572 | 0.2381 | 0.0561 | 0.7595 | 0.0472 |
| 676 | 1.3945 | 0.0640 | 0.2371 | 0.0556 | 0.7553 | 0.0525 |
| 702 | 1.3861 | 0.0578 | 0.2363 | 0.0559 | 0.7516 | 0.0538 |
Table 10.
Parameters’ average values for every cluster formed by the SOM network for the Itaigara station.
Table 10.
Parameters’ average values for every cluster formed by the SOM network for the Itaigara station.
Parameters | Parameter Average Value per Cluster |
---|
1 | 2 | 3 | 4 |
SO2 (ppb) | 0.18 | 0.09 | 0.17 | 0.89 |
CO (ppb) | 153.18 | 126.03 | 443.43 | 230.86 |
O3 (ppb) | 11.93 | 7.38 | 5.45 | 7.61 |
PM10 () | 17.73 | 12.92 | 17.97 | 15.83 |
NO (ppb) | 9.20 | 9.15 | 29.64 | 19.28 |
NO2 (ppb) | 6.10 | 6.81 | 12.29 | 9.10 |
WS (m/s) | 4.15 | 1.83 | 2.26 | 2.20 |
TEMP (°C) | 26.44 | 24.10 | 24.80 | 23.97 |
RH (%) | 64.30 | 76.97 | 73.15 | 74.38 |
STWD (°) | 21.59 | 26.16 | 26.39 | 23.43 |
#Samples | 5240 | 4469 | 3799 | 2027 |
Table 11.
Parameters average values for every cluster formed by the SOM network for the Barros Reis station.
Table 11.
Parameters average values for every cluster formed by the SOM network for the Barros Reis station.
Parameters | Parameter Average Value per Cluster |
---|
1 | 2 | 3 |
SO2 (ppb) | 0.28 | 0.64 | 0.59 |
CO (ppb) | 442.11 | 973.00 | 621.71 |
O3 (ppb) | 5.42 | 3.03 | 7.07 |
PM10 () | 33.31 | 54.00 | 42.13 |
NO (ppb) | 37.54 | 91.22 | 51.88 |
NO2 (ppb) | 10.74 | 20.23 | 15.68 |
WS (m/s) | 1.93 | 1.93 | 4.12 |
TEMP (°C) | 24.66 | 24.74 | 27.68 |
RH (%) | 72.64 | 72.19 | 60.05 |
STWD (°) | 32.73 | 31.04 | 30.19 |
#Samples | 10,599 | 4183 | 6777 |
Table 12.
Parameters average values for every cluster formed by the SOM network for the Campo Grande station.
Table 12.
Parameters average values for every cluster formed by the SOM network for the Campo Grande station.
Parameters | Parameter Average Value per Cluster |
---|
1 | 2 | 3 | 4 | 5 |
SO2 (ppb) | 0.14 | 0.26 | 0.23 | 0.38 | 0.82 |
CO (ppb) | 250.98 | 269.62 | 456.78 | 655.67 | 404.37 |
O3 (ppb) | 6.12 | 7.07 | 6.59 | 4.15 | 5.72 |
PM10 () | 20.01 | 23.71 | 17.64 | 24.45 | 22.21 |
NO (ppb) | 15.07 | 18.97 | 30.47 | 56.49 | 24.42 |
NO2 (ppb) | 10.34 | 11.12 | 14.33 | 19.15 | 13.12 |
WS (m/s) | 0.89 | 2.70 | 1.40 | 1.36 | 0.94 |
TEMP (°C) | 25.21 | 25.73 | 29.22 | 26.26 | 26.90 |
RH (%) | 77.31 | 75.14 | 61.52 | 73.56 | 68.58 |
STWD (°) | 57.82 | 42.83 | 53.05 | 50.50 | 52.28 |
#Samples | 6640 | 4166 | 6223 | 4229 | 3301 |
Table 13.
Parameters average values for every cluster formed by the SOM network for the Dique do Tororó station.
Table 13.
Parameters average values for every cluster formed by the SOM network for the Dique do Tororó station.
Parameters | Parameter Average Value per Cluster |
---|
1 | 2 | 3 |
SO2 (ppb) | 0.30 | 0.36 | 0.34 |
CO (ppb) | 245.23 | 342.03 | 130.06 |
O3 (ppb) | 9.68 | 5.18 | 6.05 |
PM10 () | 21.23 | 29.66 | 18.23 |
NO (ppb) | 15.14 | 20.06 | 3.91 |
NO2 (ppb) | 8.71 | 12.13 | 5.45 |
WS (m/s) | 2.23 | 0.67 | 0.66 |
TEMP (°C) | 26.90 | 27.22 | 24.40 |
RH (%) | 69.65 | 71.88 | 81.69 |
STWD (°) | 29.18 | 60.49 | 47.53 |
#Samples | 26,101 | 7511 | 8425 |