openaq / openaq-fetch

A tool to collect data for OpenAQ platform.
MIT License
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New El Salvador PM2.5 data #681

Open RocketD0g opened 4 years ago

RocketD0g commented 4 years ago

Ran across El Salvador AQ data:

http://www.snet.gob.sv/googlemaps/calidadaire/monitoreo2.php

As far as I can tell:

mciethan commented 2 years ago

According to the source code for this webpage, the PM2.5 numbers are 24-hour averages. The page source code also has coordinate information and URLs that may be helpful for scraping the data for each of the three stations:

station code station name long lat data URL for PM2.5 24h average
SLV1 San Salvador Centro 13.70630556 -89.20011667 http://www.snet.gob.sv/googlemaps/calidadaire/get_icca.php?estacion=SLV1
SLV2 San Salvador Este 13.71518889 -89.15481944 http://www.snet.gob.sv/googlemaps/calidadaire/get_icca.php?estacion=SLV2
SLV3 San Salvador Oeste 13.687374 -89.232255 http://www.snet.gob.sv/googlemaps/calidadaire/get_icca.php?estacion=SLV3

In addition to showing the 24-hour average PM2.5, the page has a chart showing hourly air quality index data for each station for the most recent 24 hours. Those data also have a consistent URL format (e.g., http://www.snet.gob.sv/googlemaps/calidadaire/datos24h2.php?estacion=SLV2 ), but they are index numbers, not physical PM2.5 measurements. The source code for the webpage does include the formulas for calculating their air quality index from PM2.5, though, so it might be feasible to reverse engineer hourly PM2.5 data.