Analysis
Pollution levels of a city (Representative image).
Cities of Rajasthan are experiencing rising particulate pollution and also witnessing a multi-pollutant problem with levels of several gaseous pollutants such as nitrogen dioxide (NO2) and ozone beginning to rise.
This increases public health risk in the state. This has emerged from a new analysis carried out by New Delhi-based think tank Centre for Science and Environment’s (CSE) Urban Lab.
The analysis has assessed the longer term trends as well as seasonal variations in particulate and gaseous pollution in the state.
"Air quality is worsening not only in non-attainment cities but also in smaller cities and towns of Rajasthan despite the clean air action underway. Time-bound improvement in air quality requires state-wide action to improve systems and infrastructure in all the key sectors of pollution including industry, vehicles and transport, clean energy, management of waste streams, construction and greening," said Anumita Roychowdhury, executive director, research and advocacy, CSE, while releasing the analysis on Saturday.
She said "Allocate resources equitably for the priority measures in key sectors with a strong compliance framework to meet the clean air targets”.
"Further expansion and strengthening of air quality monitoring will help to assess the growing risk better. The continuing elevated pollution levels among city stations highlight the systemic pollution that persists in the region due to inadequate infrastructure and systems for pollution control across all sectors. This can only be addressed through stringent and uniform action, round-the-year, to meet clean air standards,” says Avikal Somvanshi, senior programme manager, Urban Lab,CSE.
Data used in the analysis: This analysis is of real-time data from monitoring stations in Rajasthan for the period 1 January 2019 to 31 May 2023. This is an assessment of annual and seasonal trends in PM2.5, PM10, NO2, ground-level ozone and CO concentration for the mentioned period.
The analysis is based on real time data available from the current working air quality monitoring stations in Rajasthan. A huge volume of data points have been cleaned and data gaps have been addressed based on USEPA method for this analysis.
This analysis covers 42 continuous ambient air quality monitoring stations (CAAQMS) spread across cities of Rajasthan. Jaipur (5), Jodhpur (5) and Kota (3) have more than one real-time station, therefore citywide average is used for comparative analysis and it is defined as average of all city stations.
Key findings of the CSE analysis
In the first half of 2023, 32 new real-time and 18 new manual stations have become operational bringing the total to 99 stations. These stations are spread across 33 cities. Most of the stations -- 30 manual and 15 real-time -- are located in the five non-attainment cities of Alwar, Jaipur, Jodhpur, Kota and Udaipur.
Many cities exceed the standards for particulate pollution: Both PM10 and PM2.5 are a challenge in the state. Jodhpur is the most polluted among the five non-attainment cities, with three-year average for PM2.5 of 71 microgramme per cubic metre (µg/m3) and for PM10 of 153 µg/m3. Kota is the second most polluted with a three-year average for PM2.5 of 55 µg/m3 and for PM10 of 105 µg/m3. Jaipur is a close third with a three-year average for PM2.5 of 52 µg/m3 and for PM10 of 114 µg/m3.
Udaipur and Alwar also exceed the standard -- their three-year average for PM2.5 stands at 50 µg/m3 and 42 µg/m3, respectively. PM2.5 reduction targets vary between 4 per cent and 43 per cent for these non-attainment cities Reduction targets for PM10 are much higher, ranging between 30 and 61 per cent.
Particulate pollution is on the rise in Jaipur, Kota and Udaipur -- the 2022 average levels have crossed the pre-pandemic levels: Both PM2.5 and PM10 levels are worsening in Jaipur, Kota and Udaipur. PM2.5 level in 2022 has been 14-18 per cent higher than the level recorded in 2019 among these three cities.
NO2 pollution is on the rise in Jaipur, Jodhpur and Udaipur -- 2022 levels have crossed the pre-pandemic level: Even though the NO2 levels are lower than the national ambient air quality standards in cities of Rajasthan, the cities are witnessing a rising trend. NO2 levels are worsening in Jaipur, Jodhpur and Udaipur.
The level has been 24-51 per cent higher than what was recorded in 2019 in these three cities. It has been exceptionally challenging in Jaipur in 2022 when the NO2 level breeched the annual standard. Alwar and Kota show a stable trend.This pollutant requires early and preventive action as growing motorisation can skew the curve.
NO2 pollution is closely linked with traffic flow: The evening peak is higher in Jaipur, Jodhpur, Kota and Udaipur, while the morning peak is higher in Alwar. This indicates the impact of motorisation.
A range of gases including NO2, volatile organic compounds, carbon monoxide and others that are emitted from vehicles and industries react with each other in the air under the influence of sunlight to form ozone. This is a highly reactive gas and extremely harmful for those suffering from asthma and respiratory conditions. To control it, all other gases will have to be controlled.
The way forward
Somvanshi says, “It is necessary to scale up with speed the implementation of the multi-sector clean air action plan at the city and the state levels. The implementation of clean air action plans for the non-attainment cities as well as state clean air action plan are already underway. This will require further enhancement to strengthen the sectoral strategies to meet the sectoral targets".