Qualité de l’air à Thiruvananthapuram

How polluted is the air in Thiruvananthapuram?

Thiruvananthapuram, otherwise known by its former name of Trivandrum, is a city located in the far southern region of India, within the state of Kerala. It is a prominent hub for many academic, industrial and information technology based businesses and institutions, with a population of just below a million people as of 2011.

In June of 2021, Thiruvananthapuram presented with a US AQI reading of 60, placing it in the 'moderate' ratings bracket, color coded as yellow and requiring a US AQI reading of anywhere between 51 to 100. This indicates that at the time this air quality reading was taken, there would be mild amounts of pollution in the air, and the general public would remain largely unaffected.

However, as was seen on record, there are times of the year in which the pollution level in Thiruvananthapuram goes up significantly, and as such hourly updates can be followed via the use of air quality maps on the IQAir website, as well as via the AirVisual app.

Why does Thiruvananthapuram have higher pollution levels?

Thiruvananthapuram has a large amount of its pollution emanating from the various combustion sites that take place throughout the city, with many of these processes giving out heavy amounts of dangerous ultrafine (PM2.5) and coarse (PM10) particulate matter, with the ultrafine PM2.5 being of significantly more danger to one’s health, as was touched on above.

Furthermore, a large amount of chemical compounds are also released into the air, which beyond causing a wide variety of adverse health effects on the citizens of Thiruvananthapuram, also causes gradual damage to the buildings of the city, along with also causing harm to wildlife and vegetation, hence showing how reaching and damaging effects of pollution are, beyond that of just affecting human health.

Whilst PM2.5 levels remain fairly high, Thiruvananthapuram has shown signs of improvement in recent years regarding its overall yearly pollution levels.

In 2018, Thiruvananthapuram came in with a PM2.5 yearly average of 28 μg/m³, followed by 27.9 μg/m³ in 2019. Its 2020 average came in at 25.6 μg/m³, showing a definitive improvement over the span of a few years. However, this reading was still high enough to place it in 535^th place out of all cities ranked worldwide as of 2020, and as such if further reductions are kept up consistently in the coming years, Thiruvananthapuram may indeed be able to rank higher on the global circuit.

Going back once again to the main contributors of higher pollution levels, ones such as emissions from vehicle’s would be most prominent, with a huge amount of tuk tuk’s, motorbikes and cars inhabiting the road throughout the course of the day, as well as at night, thus giving out large and consistent volumes of noxious exhaust fumes that contain a wide array of pollutants.

These include ones such such as black carbon (which is the main component of soot, often found caking roadside areas that see a high level of vehicle usage, such as near motorways or rush hour traffic zones) and many others, which will be discussed further in the article.

Other prominent causes of pollution in Muzaffarnagar include the burning of refuse or waste, which can cause highly dangerous clouds of smoke to accumulate over the city and sometimes remain trapped within the urban infrastructure, with meteorological conditions such as lack of strong winds (as well as periods of less rain, which is also an important element in tamping down larger pollution particles in the air) can lead to high volumes that have further debilitating effects on the population as a whole.

Other sources of air pollution come from ones such as construction sites, along with road repairs, with both of them potentially releasing large amounts of dust particles, finely ground silica and other dangerous particles into the air, many of which carry a number of adverse health effects when inhaled.

Lastly, the burning of charcoal and firewood as well as dried animal dung can contribute further to pollution elevations, with such practices still taking places in many traditional homes or lower income districts. All of these aforementioned factors can compound each other, leading to the heightened levels of air pollution on record.

When are the pollution levels at their highest in Thiruvananthapuram?

The months that were recorded over 2020 showed that January, February and December all came in with the highest readings of PM2.5, presenting with numbers of 32.3 μg/m³, 35.4 μg/m³ and 34.6 μg/m³ respectively.

What are the pollutants that can be found in the air in Thiruvananthapuram?

With higher levels of air pollution present throughout the course of the year, with certain months going up even higher than the yearly average, the atmosphere during such periods would typically hold a large number of harmful pollutants and hazardous particles.

Among them would be ones that are found making up the US AQI aggregate, which includes nitrogen dioxide (NO₂), sulfur dioxide (SO₂) and ozone (O₃), a pollutant that is formed from a reaction between the various oxides of nitrogen (NOx), as well various other gases in the air. These pollutants, when subject to solar radiation, or higher levels of sunlight (which are found in abundance in the region), undergo a chemical reaction that creates ozone, or smog as it is more commonly known as, when it forms on ground level.

Other pollutants in Thiruvananthapuram include toxic metals such as lead and mercury, along with dioxins, furans and polycyclic aromatic hydrocarbons. Pollutants that typically see a large amount of release from vehicles are ones such as the aforementioned nitrogen dioxide and sulfur dioxide, with NO₂ being both a primary and secondary pollutant.

Regarding particle pollution, the previously mentioned black carbon would be permeating the atmosphere, along with other polluting particles such as gravel, road dust and finely ground silica, with the latter having carcinogenic properties, as well as being able to cause scarring of the lungs when breathed excessively or over long periods of time.

What time of the year does Thiruvananthapuram have the best air quality?

Observing the levels of PM2.5 taken over the course of 2020 once again, it can be seen that whilst not a single month moved out of the 'moderate' ratings bracket and down into a better ranking, the months of May, July and September all came in with relatively lower levels of PM2.5.

Their respective readings were 18.6 μg/m³, 19.5 μg/m³ and 19.6 μg/m³, making May the cleanest month out of the year in 2020.