Air pollution poses the second largest risk factor for premature deaths in Rajasthan. Health cost of air pollution in Rajasthan is 1.70 per cent of the state GDP – higher than the national tally of 1.36 per cent. If air pollution concentration could be lowered, life expectancy in Rajasthan could increase by 2.5 years
New Delhi, December 28, 2020: New analysis of winter air pollution (till December 20, 2020) in Rajasthan, done by Centre for Science and Environment (CSE), shows how clean air gains of the lockdown and monsoon periods were lost with the reopening of the economy and hostile winter weather. While this was expected, the analysis of the real-time data from monitoring stations across Jaipur division as well as other major cities in Rajasthan show the changing pattern in winter pollution this year. While trapping of winter pollution in Rajasthan is not as high as that of the Indo-Gangetic Plain, it increases during winter.
Even though the overall average level of PM2.5 for 2020 (up till 20 Dec) is lower than the previous year due to the summer lockdown, PM2.5 levels in winter rose beyond the standard in Jaipur and rest of Rajasthan. But this year, this trend has set in almost a week earlier in the season, and average PM2.5 levels in November have been 26-33 per cent higher in Jaipur division compared to previous November. The combination of reopening of the economy and changing meteorology is said to be responsible for this.
Says Anumita Roychowdhury, CSE executive director-research and advocacy: “This is a typical and predictable winter trend when continuous emissions from local sources including vehicles, industry, construction, and episodic pollution from biomass burning get trapped due to meteorological changes. But this year, there is higher pollution peak and substantial increase after the reopening of the economy. This demands speed, scale and urgency of action.”
Avikal Somvanshi, programme manager in CSE’s Urban Lab team of Sustainable Cities programme, says: “This detailed data analysis points to the fact that the air pollution is a more pervasive problem in this region and beyond, and this requires quicker reforms and action in key sectors of pollution – vehicles, industry, power plants and waste management to control winter pollution and further bend the annual air pollution curve.”
Access CSE’s note on the analysis here: https://cdn.cseindia.org/userfiles/Rajasthan-note-winter-pollution.pdf
Data used in the analysis: The analysis is based on publicly available granular real time data (15-minute averages) from the Central Pollution Control Board’s (CPCB) official online portal Central Control Room for Air Quality Management. Eight cities – Ajmer, Jodhpur, Kota, Pali, Udaipur, Alwar, Bhiwadi, and Jaipur have been selected for this analysis because real time data is available for these cities. This has analysed data recorded by three air quality monitoring stations at Jaipur and one station each Ajmer, Jodhpur, Kota, Pali, Udaipur, Alwar, and Bhiwadi under the Continuous Ambient Air Quality Monitoring System (CAAQMS) of CPCB. Weather data for Jaipur has been sourced from the Sanganer weather station of India Meteorological Department (IMD).
Key highlights of CSE’s analysis:
Average level of PM2.5 has been lower during this year due to the lockdown but could not prevent the winter spike: The overall PM2.5 average this year (until 20 December) has been predictably lower compared to the previous year largely because of the unprecedented economic disruption during the summer lockdown and monsoon. But reopening of the economy coinciding with the onset of the winter trapping pollution made PM2.5 levels rose starting October. From the respective cleanest week the weekly average of PM2.5 in Jaipur rose 7 times, in Ajmer 5 times, Alwar 4 times, Bhiwadi 9 times, Kota 8 times, Jodhpur 4 times, Pali 3 times, and Udaipur 4 times to the dirtiest week.
Dirtiest week for all cities was on the week ending on 15 November 2020 except in Bhiwadi which was a week earlier. Cleanest week for Alwar and Pali was in the early April, 2020. Ajmer and Kota had their cleanest week on the week ending 12 July 2020. Udaipur, Jaipur and Bhiwadi had their cleanest week in August 2020. Jodhpur had its cleanest week on the week ending 6 September 2020. The transient change of the lockdown phases could not be sustained without the systemic changes needed to control pollution from vehicles, industry, power plants, and waste.
Average November PM2.5 level has been considerably higher this year: November this year was dirtier across all cities in Rajasthan. The PM2.5 average this November was 26 per cent higher in Jaipur, 33 per cent in Alwar and Bhiwadi compared to November 2019. November was also dirtier in other cities 6 per cent in Pali, 6 per cent in Ajmer, 8 per cent in Udaipur, 33 per cent in Kota and 55 per cent in Jodhpur. August this year was 13-47 per cent cleaner in these cities compared to August 2019.
Air quality gets more toxic with the onset of winter -- share of tinier PM2.5 in the PM10 increases: The share of tinier and finer particles in the overall coarser PM10 concentration determines the toxicity of air. When the overall share of tinier PM2.5 in the overall coarser PM10 is higher, the air is more toxic as the tiny particles penetrate deep inside the lungs and cut through the blood barrier increasing health risk. Interestingly, during lockdown, when the overall suspended coarser particles had settled down reducing the PM10 levels, the PM2.5 had also come down. But its share was 40 per cent in April – higher than it’s usually noted during summer (April 2019 was 35 per cent). But with the onset of winter the overall level of both have gone up and also the percentage share of PM2.5 in the overall PM10. This rose to above 50 per cent during mid-October and remained high through November averaging at 53 per cent. The share of PM2.5 in PM10 is generally highest on Diwali and it peaked at 70 per cent this year but it was a week before Diwali.
Diwali was cleaner in Jaipur but dirtier in Jodhpur this year: The average PM2.5 level on day after Diwali in Jaipur was 72 μg/m3 down from 211 μg/m3 recorded in 2019, 66 per cent decline. This year there was about 85 per cent lower rise in hourly PM2.5 concentration between afternoon and night of Diwali that is mostly caused due to firecracker busting. But story was different in Jodhpur where the change in hourly PM2.5 concentration between afternoon and night of 2020 Diwali was 379 μg/m3, up from 244 μg/m3 in 2019. The average PM2.5 level on day after Diwali in Jodhpur was 149 μg/m3 up from 123 μg/m3 recorded in 2019, 21 per cent increase. This Diwali also occurred later in November than the previous year.
Jaipur – this winter had the dirtiest week in three years: The rolling weekly average rose over the 24hr standard or 60 μg/m3 on October 20, but it did so on October 25 last year. This year the rolling weekly average crossed “Very Poor” level or 120 μg/m3 on November 10 and remained over till November 15. Rolling weekly average had never crossed 120 μg/m3 in 2018 or 2019.
Jaipur – city-wide number of days with PM2.5 concentration in poor or worse category was considerably higher this winter: There have been 5 days of “very poor” air days this winter compared to just 4 recorded last year and zero in 2018. The “poor” days have also increased to 10 days from 3 days last year.
Jaipur: Episodes of bad air quality are becoming increasingly longer and severe in Jaipur during winter: This inelastic behavior of PM2.5 levels in Jaipur is in contrast to the trend seen in Delhi-NCR where the trend has been more volatile during winter with frequent quicker rise and drop. This can be the impact of changed meteorology but more investigation is needed to understand the reasons for this.
Even with comparatively cleaner air during this year, Rajasthan cities recorded daily spikes similar to those observed in 2019: CSE has compared the annual averages and peak 24hr averages in these cities of Rajasthan between 2019 and 2020. This shows that eastern Rajasthan cities even with much lower annual average levels of PM2.5 have experienced almost same or higher maximum daily levels during winter when the entire region got air locked. Cities in western and central Rajasthan have registered much lower daily spikes.
Jaipur faced the impact of stubble smoke smog this year: CSE tracked stubble fire smog movement down the Indo-Gangetic Plain by looking for unusual spike in PM2.5 levels at CAAQM stations in the region. Last year when peak smog hit IGP in first week of November Rajasthan cities showed no unusual spike in their PM2.5 except Bhiwadi which is very close to Delhi. In fact, the peak PM2.5 in Jaipur and Jodhpur in 2019 happened before smog started in IGP. But this year the peak PM2.5 in Jaipur and Jodhpur aligned smog. Peak of smog happened on 9 November in Delhi with PM2.5 at 520 μg/m3 interestingly Jaipur recorded its peak (211 μg/m3) a day later on 10 November and Jodhpur registered its peak (156 μg/m3) on 11 November. This is highly unusual and needs further investigation (that is beyond the scope of this analysis) as the regular wind patterns are not known to blow the stubble smoke towards Thar Desert.
Need deep cuts
To avoid winter pollution peaks all cities of Rajasthan will have to reduce the annual average level of pollution to meet the national ambient air quality standards and even bring it further down to be closure to health based guidelines of the World Health Organisation. CSE analysis shows that while annual average PM2.5 level in Jaipur will have to be reduced by 23 per cent to meet the national ambient air quality standards for PM2.5, Jodhpur by 54 per cent, Bhiwadi by 64 per cent, Pali by 34 per cent and Always by 16 per cent. This demands very stringent action.
Already, the new LANCET 2020 study has shown that while the health cost of air pollution is about 1.36 per cent of the national GDP of India, it is 1.70 per cent of the state GDP of Rajasthan – which is higher than the national tally. According to the state-level disease burden estimates by IHME, ICMR and PHFI air pollution ranks as the second-largest risk factor for premature deaths in Rajasthan. If air pollution concentration could be lowered, the life expectancy in Rajasthan could increase by 2.5 years. The cumulative effect of this population-wide can be big.
How the pollution level will play out during the rest of the winter remains to be seen. But it is clear that the region has to take forward its wins so far and raise the level of ambition to drive action across all key sectors of pollution and in the entire region. Enforce power plant standards across the state, minimise use of coal and other dirt fuels in the industry while improving emissions control, scale up public transport and vehicle restraint measures and manage waste to have a zero waste and zero landfill strategy.
To speak to an expert on this issue, contact: Sukanya Nair of The CSE Media Resource Centre, firstname.lastname@example.org, 8816818864