 "Delhi's air pollution rises 23% during second odd-even phase")
Air pollution levels in Delhi rose 23 per cent during the second phase of the odd-even registration rule, from April 15 to April 29, over the previous 14 days (April 1 to April 14), based on an analysis of PM (particulate matter) 2.5 data, generated by IndiaSpend's #Breathe air-quality monitoring devices.
The odd-even scheme ended on Saturday, April 30, the data indicating that it likely cannot work in the long term without additional actions, such as improving bus services, curbing factory and truck emissions and suppressing construction dust, which accounts for about half of Delhi's air pollution. Wind speed and temperature also affect air quality.
Read more from our special coverage on "ODD-EVEN SCHEME"
The average PM 2.5 concentration in Delhi's air was 68.98 micrograms per cubic metre (µg/m³) during the odd-even period, from April 15 to April 29, indicating "moderate" conditions, which increased from 56.17µg/m³, indicating "average" air quality between April 1 and April 14.
Similarly, average PM 10 concentration before the odd-even period was 110.04 µg/m³ (April 1 to April 15), rising 22 per cent into the odd-even phase to 134.39µg/m³ (April 15 to April 29), indicating 'moderate' air quality.
Evening 5 pm was the best hour for Delhi during the odd-even phase, with PM 2.5 levels at 21µg/m3, indicating "good" air quality.
Similarly, the PM 10 levels during 7 am were as high as 243.967µg/m3, indicating "moderate" conditions, which cause respiratory illness on prolonged exposure. These levels rose 36% from 179.7 µg/m³ at 7 am, based on hourly averages of the 15 days preceding the odd-even period.
Mornings recorded the worst air pollution in four Indian cities-Bengaluru, Chennai, Delhi and Mumbai - based on analysis of PM 2.5 data, IndiaSpend reported recently.
Getting a reliable picture of air pollution is inherently difficult due to Delhi's changing weather conditions and constantly shifting patterns of emissions throughout the day, week, and year, IndiaSpend had reported. Moreover, some of the most important pollution sources lie outside the National Capital Region.
A growing tide of vehicles and pollution in Delhi, falling use of buses
Outdoor air pollution causes 670,000 deaths annually in India, according to this 2014 research paper from the Indian Institute of Management, Ahmedabad. The second phase of odd-even reported fewer violators-5,814 during the first 10 days, compared to the first phase (6,768). Violators were fined Rs 2,000.
Vehicles per 1,000 people in Delhi have increased 92 per cent over the past 16 years, as bus and ridership declined, according to Delhi's Economic Survey 2014-15. Daily passenger ridership on Delhi Transport Corporation (DTC) buses declined 11 per cent in 2014-15 over the previous year, and the number of buses has declined 24 per cent over the past five years, from 6,204 in 2010-11 to 4,712 in 2014-15, IndiaSpend reported. Boosting bus services, we also observed, is key to sustaining the odd-even system. Delhi was reported to have more than 8.8 million motor vehicles as on March 31, 2015, registering an increase of more than 6 per cent over the previous year.Two-wheelers (motor cycles and scooters) reported a growth of over 7 per cent in 2014-15, followed by taxis (6 per cent) and cars and jeeps (6 per cent). The use of other passenger vehicles, such as tractors, fell.
Delhi's transport sector produces six times as much greenhouse gas emissions (GHG) as that of Kolkata's, five times as much as Ahmedabad's and three times as much as Greater Mumbai and Chennai, IndiaSpend had reported earlier.
Heavy vehicles are major sources of PM 10 and oxides of Nitrogen (NOx). Trucks are leading polluters, contributing 46 per cent of PM 10 and 38 per cent of NOx; light commercial vehicles contribute 28 per cent of PM 10 levels and 13 per cent of NOx, as IndiaSpend reported previously.
Odd-even in other cities across the world
Mexico City started this rule as Hoy no Circula scheme (No Circulating Day) in 1989. The trial implementation during the winter months of 1989 resulted in a 20 per cent reduction in daily vehicles in circulation within the target area, an increase in vehicle speeds, drop in fuel consumption and 6.6 per centincrease in subway ridership.
Initially, the scheme reduced pollution 11 per cent. But, once the rule became permanent, people purchased more vehicles with alternate plates. There was no improvement in long-term air quality levels during any hour of the day or the week. Pollutions levels increased during the weekends and hours of the day when the rule did not apply.
In Paris, similar restrictions were imposed for one day in 1997 and in March 2014. The experiment reduced pollution levels. Beijing implemented a temporary scheme before the 2008 Summer Olympics, cleaning the air and relieving traffic congestion.
In Sao Paulo, the scheme was initially implemented in 1995, as an emergency measure to curb air pollution. An experimental trial of six month showed 2 per cent (morning) and 5 per cent (evening) reduction in peak-period vehicular volumes. The initial experiment was successful in reducing pollution levels, especially carbon monoxide. The odd-even scheme known as Rodizio, was made permanent in 1997.
Reprinted with permission from IndiaSpend.org. Indiaspend.org is a data-driven, public-interest journalism non-profit
