A study of 40 cities in 35 countries found that in most cities, invisible dust particles, PM 2.5 and PM 10, dropped sharply.
Air quality around the world has improved significantly since the Kovid-19 epidemic hit major cities. Half of the world’s people are forced to live indoors because of Kovid-19. Vehicles, factories and distilleries are closed. Improving air quality is the result.
A detailed scientific study of the changes in the environment caused by the lockdown remains to be done. Research by three researchers from the Global Institute for Interdisciplinary Studies in Nepal and three from Germany and Australia has also shown a significant reduction in air pollution in busy cities.
Dr. Asheshwarman Shrestha, Dr. Uttam Babu Shrestha, Roshan Sharma, Dr. Suraj Bhattarai, Han Tran and Dr. A joint team of Maheshwar Rupakheti has investigated the air pollution situation in 40 cities of 35 countries on all six continents. His research has just been published in the journal Pre-Print (findings before the final report). The final report is yet to be made public.
While Nepal’s research institutes and universities are in a dilemma, they have taken the lead in studying the pollution of cities around the world from Nepal.
Involved in the research, the director of the Global Institute for Interdisciplinary Studies in Nepal, Dr. Uttam Babu Shrestha told Kantipur, “We have been conducting research in Nepal for three weeks using the technology to check the air quality of the world’s cities.”
Researcher at the Global Institute for Interdisciplinary Studies in Nepal, Dr. According to Asheshwar Man Shrestha, the research compares the amount of dust particles, carbon monoxide, nitrogen dioxide, sulfur dioxide and weight in the air in February and March of this year and February and March of this year. “At the same time, we have analyzed the 100-day pollution situation and the difference caused by the lockdown,” he said. Conclusions are drawn using the data collected. ‘There is a possibility of error in the analysis done by looking at the satellite image with the naked eye,’ said the research director. Shrestha said, “We have conducted research using data collected by pollution measuring devices on the roads of 40 cities. This is probably the first study to look at the air pollution situation in many cities.”
According to Roshan Sharma, a doctoral student at RMIT University in Australia, the data was collected from 301 air pollution measuring stations in 40 cities. According to the research, the amount of invisible dust particles (PM 2.5) is less in 17 cities now than in February last year. The same particle was seen less in 14 cities this March than in March last year. “Dust levels have dropped significantly in cities like Kathmandu, Vienna, London, Amsterdam, New York and Sydney,” said Shrestha.
Research showed that PM 2.5 levels fell by 57 per cent in Vienna, 53 per cent in Paris, 47.5 per cent in Amsterdam, 45.6 per cent in London and 45.2 per cent in Dubai in February. In March, pollution was reduced by 37 percent in New York, 35 percent in Sydney, 32.2 percent in Abu Dhabi, 31 percent in Nanjing and 26 percent in Ulaanbaatar. The analysis shows that the amount of dust in Bangalore, Bangkok, Beijing, Delhi, Nanjing, Wuhan and Ulaanbaatar, which are known as the most polluted cities in the world, has decreased significantly. These cities also have significant differences in the amount of dust particles larger than 2.5 PM (PM 10).
Although the pollution in Kathmandu increased in February this year as compared to February last year, the air quality has improved significantly since March, Shrestha said. Lockdown has started in Nepal on March 24. Since the start of the lockdown, the pollution measurement centers in various parts of the country, including Kathmandu, have recorded less.
In different parts of the country, including Kathmandu, the level of PM 2.5 is currently in line with the standards set by the World Health Organization (WHO) and in some places even lower. The WHO has set the PM 2.5 dose at 25 micrograms (24 hours). The government has set the PM2.5 per cubic meter of air at 40 micrograms.
In Phagun, IQ Air also published a report on the improvement in air quality in Kathmandu this year as compared to the previous year. Last year, the amount of invisible dust particles (PM 2.5) per cubic meter of air was 54.4 micrograms per cubic meter, but this year it has dropped to 44.5 micrograms, he said.
According to Director Shrestha, the proportion of nitrogen dioxide emitted from vehicles and factories in different cities has also come down significantly. Nitrogen dioxide pollution has been reduced in 19 cities around the world since the crash. Similarly, there has been a significant reduction in carbon monoxide.
The amount of the main cause of pollution has not decreased in all the cities of the world. Pollution has increased in cities where there is no logging. Shrestha added, “Harmful chemicals like sulfur dioxide and weight have also increased or decreased.”