Mains Paper 3 | Conservation, environmental pollution and degradation, environmental impact assessment
Prelims level: System of Air quality And Weather Forecasting and Research
Mains level: This news card discusses the study by SAFAR and IMD that highlights main reason behind Delhi Smog
Reason for Delhi Smog apart from Stubble Burning
- Besides stubble burning, a “multi-day dust storm” in Iraq, Kuwait and Saudi Arabia was the main cause of Delhi’s smog between November 6 and 14.
- According to a study by the System of Air Quality And Weather Forecasting And Research(under the Ministry of Earth Sciences) and India Meteorological Department (IMD).
Key Points from the Study
- There was a large multi-day dust storm that emerged in Iraq, Kuwait and Saudi Arabia in the last week of October 2017 and continued up to November 3 and 4.
- This dust storm was carried by relatively cool winds.
- Winds at a height and low wind speed close to the surface meant that the pollutants were carried towards Delhi.
- Also, stubble burning in Punjab, Uttar Pradesh and Haryana was very high on November 6 and upper-air winds became North Westerly (towards Delhi) with high speed and started pumping pollution in Delhi.
- The study says that the dust storm was responsible for 40 percent of the pollution on November 8, when the average air quality index was 478, indicating “severe” levels of pollution.
- While stubble burning was responsible for 25 percent of the pollution, “local sources” also played a role.
What if there was no Multiday Storm?
- According to the study, if external sources had not affected air quality, the average concentration of PM 2.5 would have been about 200micrograms per cubic meter instead of 640 micrograms per cubic meter
Weather Conditions in Delhi
- The weather conditions that persisted locally between November 8 and 14 were calm winds, cool temperature, inversion layer trapped pollution within Delhi territory.
Impact of measures taken under Graded Action Plan
- According to the SAFAR and IMD report, the imposition of emergency measures such as a ban on construction and entry of trucks in Delhi made a positive difference of around 15 percent
System of Air Quality & Weather Forecasting and Research (SAFAR):
- SAFAR envisages a research-based management system where strategies of air pollution mitigation go hand in hand with nation’s economic development to target a win-win scenario.
- It helps in knowing the City Air Quality- Overall city pollution and Location specific Air Quality.
- The SAFAR system is developed by Indian Institute of Tropical Meteorology, Pune, along with ESSO partner institutions namely India Meteorological Department (IMD) and National Centre for Medium Range Weather Forecasting (NCMRWF).
- It has been introduced for greater metropolitan cities of India to provide location-specific information on air quality in near real time and its forecast 1-3 days in advance for the first time in India.
- It has been combined with the early warning system on weather parameters.
- The ultimate objective of the project is to increase awareness among general public regarding the air quality in their city well in advance so that appropriate mitigation measures and systematic action can be taken up for betterment of air quality and related health issues