The Puchuncavi-Quintero-Concon industrial complex is located on the Central coast of Chile in the communes with the same names. Currently, this area is saturated by particulate matter, although there is also monitoring of sulfur dioxide (SO2), ozone (O3), nitrogen dioxide (NO2) and carbon monoxide (CO) in different air quality monitoring stations. In this industrial zone, the inventory of emissions from industrial sources is available and detailed as an individual point source at the Chilean Pollutant Release and Transfer Registers (PRTR) website (https://retc.mma.gob.cl/). Otherwise, the annual transport emissions are reported at the commune level, but it is limited to specific areas and there is not available gridded georeferenced data. This is the main limitation for the evaluation of this source emission in studies of air quality.
This study applied the CAMS-GLOB-ANT datasets for the identification and analysis of the emissions from the transport sector. The Weather Research and Forecast (WRF) model version 4.1.2 was used to create a domain of analysis with 73 x 73 grid cells and 1 km of horizontal resolution. WRF model was run for 1 hour, and the output file was processed in the computational module Meteorology-Chemistry Interface Processor (MCIP) [9]. MCIP creates four files with the georeferenced information required by the SMOKE model and reduces 3 grid cells for each side of the domain, generating a new domain with 70 x 70 grid cells in this study.
The monthly processed files as described in the previous section were input into SMOKE as gridded data.
The spatial distribution of the emissions processed in SMOKE is shown in Fig. 2. The letters represent the communes' location in the domain of analysis. The gridded cells positioned in the ocean are explained by the resolution of the CAMS datasets files. However, the emissions processed in SMOKE can be considered acceptable and a preliminary estimation for future air quality modeling.
One of the main uncertainties for emission inventory simulation is the temporal profile of the emissions. The SMOKE output files bring the monthly fraction of transport emissions, as shown in Fig. 2. In this case, three different registries were obtained for different communes in the zone of analysis.
The highest emissions occurred during August 2018 for all communes. In contrast, the lowest fractions were observed in January, February and July, when the holiday season is present in Chile. The temporal profile obtained using CAMS datasets is reasonable except for Viña del Mar and Valparaiso. These communes received many tourists during holidays every year, impacting the transport sector and increasing the traffic on the urban streets. In January and February, the monthly profile must be higher than the rest of the year. The information shown in Fig. 3 could help future studies of emission inventories about this anthropogenic source in Chile.
Table 2
Comparison of the annual emissions from CAMS datasets and official report in Chile.
Commune
|
Sulfur dioxide
|
Carbon Monoxide
|
Methane
|
CAMS
|
Official report
|
CAMS
|
Official report
|
CAMS
|
Official report
|
Valparaiso
|
0.439
|
3.392
|
2260
|
4057
|
4.610
|
24.800
|
Viña del Mar
|
1.148
|
4.997
|
5713
|
5895
|
11.757
|
36.475
|
Quilpue
|
1.263
|
1.530
|
4466
|
2000
|
8.925
|
10.918
|
Villa Alemana
|
1.110
|
1.173
|
3674
|
1256
|
7.470
|
7.867
|
Concon
|
1.036
|
0.627
|
2154
|
1353
|
4.437
|
5.968
|
Quintero
|
0.355
|
0.142
|
961
|
217
|
1.876
|
0.622
|
Puchuncavi
|
0.489
|
-
|
1522
|
-
|
3.170
|
-
|
The CAMS datasets registries were compared to the official report from PRTR in Chile [10]. As shown in Table 2, most of the emissions recorded in Valparaiso and Viña del Mar from the global database are lower than the government estimation in Chile. Both communes are the most populated in the region and receive many flotant people every day. Otherwise, the records for Quilpue, Villa Alemana and Concon, are comparable, except for CO in Quilpue, where the CAMS dataset registered more than twice the official report. These zones are considered housing regions and their emissions from the transport sector are lower than reported in Valparaiso and Viña del Mar. Finally, the emissions recorded in Quintero from the global database are 3 times higher than the national registries. It could be explained due to the industrial sector is the most current activity in this commune. Finally, there are not official emission records for the Puchuncavi commune and the values from the CAMS dataset could be helpful for the air quality modeling in this zone. It is remarkable to distinguish that the emissions from the official report are estimated using mobile models.