Need help understanding the AQI in Goa

I'm looking for two or more people who would like to track the AQI in Goa - using a small air quality monitor that I can purchase for them - and to note the AQI in a public excel sheet once a day.

If anyone is interested, please let me know.

Here's the background for this:

- I've loved visiting Goa and want to understand what the real pollution levels are across the year, and also I have a curious mind that is drawn to figuring out important problems. A lot of people think Goa has fresh clean air, and I think that is something we need to understand better.

- I was in Goa in 2024 in June and then in September and October. The AQI levels on my monitor were relatively good in June and September (~50 - 80 Indian AQI). In October they gradually rose to 200, and sometimes 300. I left because I was feeling sick. I was in Varca but I drove around in Cavelossim-Varca-Benaulim-Margao-close to Ponda and the AQI did not change. It was also the same in Anjuna.

- The Goan government stopped sharing AQI data in late 2022. Until then the data showed AQI to be ~ 80 outside the monsoons. This was obviously a big mismatch with both my monitor and my own body's experience of being in Goa in October 2024.

- I made an RTI query about why AQI data is not shared publicly, since the law requires it to be shared and more or less every state of India shares hour to hour data here - National Air Quality Index - Goa being an exception. I got a reply that the data is being shared now. However, the data was shared for 15 days only, not hour to hour but an average of 3 days, shared once in 3 days – AQI Bulletin – Goa State Pollution Control Board - and that too stopped 2 months ago. According to their data the AQI in Goa outside monsoon is still ~ 80, but I don't trust the Goan government because of this behaviour.

- In addition to my monitor, a person in Calangute - Goa Calangute Air Quality Index (AQI) and Calangute Air Pollution | IQAir - is sharing live AQI data from his private monitor. Since mid-October, it averages at 180 AQI US which is about 240 Indian AQI. That roughly matches my monitor's figures. So either the government is giving us false data or both I and Raoul (the person running this monitor) have bad monitors, which is not possible because I've tested my monitor with a totally different one and they more or less match in their measurements.

- Other than the government's data, my monitor and Raoul's monitor, there are no on ground monitors that I know of in Goa. I am no longer in Goa, and the government is not giving us data again, and when it was, it was probably false data. So we only have one meter in all of Goa now that is reliable.

All other data we see if we Google "AQI Goa" is coming from satellite estimates based on satellite imagery, which uses the amount of light reflected back by the air as the foundation for how much particulate matter is in the air. These estimates can be wildly different from what mine and Raoul's monitors are measuring, and I would any day trust an on ground monitor than a satellite estimate. That is what governments and experts all over the world do - rely on satellite data only as a last choice.

- AQI does not change beyond ~25 points across a distance of 50 or 100 km, unless there is a specific event like a fire. The wind travels very fast and spreads particulate matter far beyond its source. This is the reason you can go to a small village in UP or Haryana and the AQI will not be better than Delhi there, even if there are very few cars and no factories. I've seen this in various other parts of the country as well. The AQI is not different between Pondicherry and a Tamil village an hour's drive from there, for example. So Calangute and Varca are fairly representative of Goa's AQI. The AQI on the beach is the same as the AQI many kilometres away from the beach, only that on the beach it may fluctuate minute to minute because of high winds, but the average is not different when I measure standing at the shore on Varca, for example and when I measure in Margao.

So, if you care about AQI and would like to figure out what the AQI in Goa truly is like, my suggestion is that 2 or more people could use this AQI monitor - Prana Air Pocket PM2.5 Monitor (WiFi) | Portable Pollution Detector - and share their data once a day on a public excel sheet. The monitor costs Rs 4000 and I can buy two of these if people are sincerely interested and promise to share data daily for one whole year and preferably longer.

If you are interested and would like to buy the monitor yourself, that's even better.

The monitor by Prana is extremely easy to use, you just switch it on and it tells you the AQI on the Indian scale. Step outside your house for 1 minute to do this because indoor readings may be influenced by things like cooking, insufficient ventilation, etc. It is accurate, because I have compared it to an Air Veda monitor and they give similar readings, and others I know have compared it to other monitors too, including high end ones.

My sense is that outside June to September, Goa's AQI is ~200, which makes it worse than Mumbai and Kolkata, and worse than Delhi's AQI outside winters. Within the monsoon period of June to September, Goa is pretty good, about 60.

PS: Please don't make this thread about blaming people X or community Y for everything that is wrong in Goa.

And I have no association with Prana Air, it is simply an inexpensive monitor that is also recommended as reliable by AQI enthusiasts. If someone wants to use other monitors to share AQI data, I have no problems with that.