India · Tamil Nadu · 33 cities
Air quality in Tamil Nadu today The AQI right now, city by city
Right now, Ooty has the cleanest air of the 33 cities we track in Tamil Nadu (AQI 66, Moderate), and Hosūr the worst (AQI 175, Unhealthy). Neyveli has the most tree cover, at 70.2% — #13 of 470 cities measured in India.
Every city is measured the same way, over the same 2 km around its center: the air quality right now, from ground stations where there are any, and its tree cover.
Average right now
AQI 137
Unhealthy for sensitive groups
- cities tracked
- 33
- average tree cover
- 29.9%
- India: 27.3%
- worst air now: Hosūr
- 175
- cleanest air now: Ooty
- 66
Lower is better on the US EPA index: 0–50 is Good, above 300 is Hazardous, and it reads differently from India's AQI (CPCB). Measured by Airleaf, refreshed hourly.
Tamil Nadu · average AQI 137
Air quality today across Tamil Nadu, city by city
| Chennai | 163Unhealthy | 22.1% | 54.9K | #276 of 470 |
|---|---|---|---|---|
| Coimbatore | 99Moderate | 25.4% | 14.2K | #209 of 470 |
| Kallakurichi | 163Unhealthy | 38.6% | 4.3K | #85 of 470 |
| Madurai | 90Moderate | 23.6% | 20.1K | #244 of 470 |
| Tirunelveli | 114Unhealthy for sensitive groups | 24.3% | 32.4K | #231 of 470 |
| Tiruchirappalli | 170Unhealthy | 26.8% | 41.5K | #187 of 470 |
| Tiruppur | 105Unhealthy for sensitive groups | 12.4% | 71.0K | #416 of 470 |
| Salem | 156Unhealthy | 15.8% | 76.0K | #365 of 470 |
| Erode | 158Unhealthy | 20.8% | 60.3K | #293 of 470 |
| Vellore | 133Unhealthy for sensitive groups | 32.4% | 8.2K | #123 of 470 |
| Ambattur | 160Unhealthy | 23.1% | 51.5K | #254 of 470 |
| Thoothukudi | 103Unhealthy for sensitive groups | 13.1% | 36.1K | #407 of 470 |
| Dindigul | 89Moderate | 23.1% | 21.7K | #253 of 470 |
| Thanjavur | 161Unhealthy | 33.6% | 20.1K | #114 of 470 |
| Rānipet | 154Unhealthy | 38.5% | 4.7K | #86 of 470 |
| Tiruvottiyūr | 163Unhealthy | 22.5% | 35.5K | #263 of 470 |
| Sivakasi | 84Moderate | 20.0% | 31.4K | #302 of 470 |
| Karur | 153Unhealthy | 29.6% | 32.7K | #145 of 470 |
| Pallāvaram | 145Unhealthy for sensitive groups | 29.2% | 18.1K | #149 of 470 |
| Ooty | 66Moderate | 45.3% | — | #49 of 470 |
| Hosūr | 175Unhealthy | 20.6% | 60.4K | #295 of 470 |
| Nāgercoil | 83Moderate | 40.9% | — | #69 of 470 |
| Kanchipuram | 156Unhealthy | 35.8% | 13.2K | #103 of 470 |
| Kumarapalayam | 173Unhealthy | 17.5% | 70.4K | #345 of 470 |
| Kāraikkudi | 139Unhealthy for sensitive groups | 44.5% | — | #56 of 470 |
| Neyveli | 155Unhealthy | 70.2% | — | #13 of 470 |
| Cuddalore | 165Unhealthy | 27.8% | 37.1K | #167 of 470 |
| Kumbakonam | 161Unhealthy | 48.6% | — | #44 of 470 |
| Tiruvannamalai | 159Unhealthy | 38.4% | 5.0K | #87 of 470 |
| Rajapalayam | 115Unhealthy for sensitive groups | 22.3% | 39.9K | #268 of 470 |
| Pudukkottai | 163Unhealthy | 24.6% | 48.3K | #223 of 470 |
| Ambur | 153Unhealthy | 44.4% | — | #57 of 470 |
| Nagapattinam | 88Moderate | 29.6% | 862 | #144 of 470 |
Air quality is the US AQI from ground monitoring stations via OpenAQ where available, otherwise the Open-Meteo / CAMS model, refreshed hourly. Tree cover is measured within 2 km of each city center from Sentinel-2 imagery; the rank compares every city measured in India.
Is this the same as India's AQI (CPCB)?
No. Airleaf shows the US EPA Air Quality Index (AQI), the scale used by IQAir and most air-quality apps. India's Central Pollution Control Board (CPCB) publishes the National Air Quality Index on its own scale: 0–50 good, 51–100 satisfactory, 101–200 moderate, 201–300 poor, 301–400 very poor and 401–500 severe. The two scales don't line up. At moderate fine-particle levels the US scale reads higher: 55 µg/m³ of PM2.5 is 149 on the US AQI but about 92, "satisfactory", on India's. In heavy smog India's reads higher: 100 µg/m³ is 182 on the US AQI and about 232, "poor", on India's. CPCB also averages particles over 24 hours, so its figure moves more slowly than an hourly reading.
India's AQI (CPCB) and the AQI, explainedDeforestation · 2001–2025
How much forest has Tamil Nadu lost?
Since 2001, Tamil Nadu has lost about 34,700 hectares of forest (about 49,000 football pitches): 2.9% of the forest it had in 2000. Most of it (75%) was deforestation, forest cleared for good, mainly for farms, pasture and plantations.
- Forest lost since 2001
- 34,700 haabout 49,000 football pitches
- Share of its forest
- 2.9%of what there was in 2000
- Cleared for good
- 26,000 hadeforestation: turned into farms, mines or towns
Hectares of forest lost each year
Show the figures as a table
| Year | Cleared for good | Can grow back | Total |
|---|---|---|---|
| 2001 | 1,680 ha | 463 ha | 2,140 ha |
| 2002 | 816 ha | 342 ha | 1,160 ha |
| 2003 | 394 ha | 161 ha | 555 ha |
| 2004 | 673 ha | 579 ha | 1,250 ha |
| 2005 | 683 ha | 282 ha | 965 ha |
| 2006 | 1,130 ha | 493 ha | 1,620 ha |
| 2007 | 1,180 ha | 557 ha | 1,740 ha |
| 2008 | 1,100 ha | 230 ha | 1,330 ha |
| 2009 | 340 ha | 118 ha | 458 ha |
| 2010 | 76 ha | 17 ha | 92 ha |
| 2011 | 966 ha | 314 ha | 1,280 ha |
| 2012 | 1,290 ha | 377 ha | 1,670 ha |
| 2013 | 429 ha | 156 ha | 585 ha |
| 2014 | 748 ha | 269 ha | 1,020 ha |
| 2015 | 816 ha | 174 ha | 990 ha |
| 2016 | 1,130 ha | 176 ha | 1,300 ha |
| 2017 | 1,420 ha | 124 ha | 1,550 ha |
| 2018 | 1,690 ha | 328 ha | 2,020 ha |
| 2019 | 1,330 ha | 716 ha | 2,040 ha |
| 2020 | 1,100 ha | 184 ha | 1,280 ha |
| 2021 | 1,040 ha | 140 ha | 1,180 ha |
| 2022 | 935 ha | 122 ha | 1,060 ha |
| 2023 | 1,720 ha | 443 ha | 2,160 ha |
| 2024 | 1,480 ha | 1,480 ha | 2,960 ha |
| 2025 | 1,820 ha | 515 ha | 2,330 ha |
Forest loss has stayed about the same: about 1,940 hectares a year in 2021–2025, against 1,640 hectares a year in 2016–2020. The worst year was 2024, when about 2,960 hectares of forest were lost.
What is causing deforestation in Tamil Nadu?
- Farms, pasture and plantationscleared for good72% · 24,900 ha
- Loggingcan grow back11% · 3,970 ha
- Wildfirescan grow back6.1% · 2,140 ha
Also: towns and roads, shifting farming, storms, floods and other natural causes, mining and energy, unknown causes.
Causes for 2025 are estimates, based on what caused forest loss in the same places up to 2024.
Source: Hansen/UMD/Google/USGS/NASA, Global Forest Change (GFC-2025-v1.13); causes: WRI/Google DeepMind drivers of forest loss; both CC BY 4.0, summed by Airleaf for each area. How it's measured
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