Delhi, Mumbai and Kolkata are in the top 10 world’s most polluted cities, while India as a nation is reported as the third most populated country after Bangladesh and Pakistan. However, overall air quality has improved in 65 percent of the global cities in 2020 amid the COVID-19 pandemic. The data has been published by IQAir in its World Air Quality Report 2020 in March 2021.
This article mentions the key findings of the 2020 World Air Quality Report. The information can be useful for the IAS Exam among other competitive examinations.
Get the list and notes PDF of international organizations’ reports in the linked article.
|Similar to the World Air Quality Report, there are various global reports that are a must-read for Civil Services Examination preparation:|
About World Air Quality Report for UPSC
- It is published by a Swiss Organization, IQAir.
- It is published globally.
- In 2020, it assessed PM 2.5 average across 106 countries.
- In 2019 and 2018, the number of countries evaluated for their air quality were 98 and 69 respectively.
- The organization compares PM 2.5 levels across the globe by ground-level monitoring stations in real-time. Only PM2.5 monitoring stations with high data availability have been included.
- The two guidelines as used by the report are:
- World Health Organization (WHO) Air Quality Guideline for annual PM2.5 exposure – This guideline states that an annual exposure of PM 2.5 that is less than 10 μg/m³ minimizes health risks.
- The United States Air Quality Index (US AQI)
- It used to visualize PM 2.5 levels that exceed the WHO target of 10 μg/m³.
- There are six US AQI levels: – Good, Moderate, Unhealthy for Sensitive Groups, Unhealthy, Very Unhealthy, and Hazardous.
Significance of PM 2.5
- The Particulate Matter which is 2.5 microns or less in width is called PM 2.5. Given their size, they get easily absorbed deep into the bloodstream upon inhalation. It results in adverse health effects.
- According to IQAir, PM 2.5 is the most harmful air pollutant.
- The adverse effects of PM 2.5 on human health are significant and include cardiovascular disease, respiratory illness, and premature mortality.
- The common human-made sources that generate PM 2.5 are:
- Fossil-fuel powered motor vehicles
- Power generation
- Industrial activity
- Biomass burning
Read about air pollutants, their types and classification in the linked article.
Key Findings of the 2020 World Air Quality Report
- Premature Deaths – Air pollution causes 7 million early deaths annually.
- Economic Burden – Air pollution causes a loss of 3.3% of the global GDP due to fossil fuel emissions.
- Out of the 50 most polluted cities, 49 cities are in Bangladesh, China, India, and Pakistan.
- 2020 is the year of a significant decrease in air pollution due to the lockdown imposed across cities to arrest the COVID-19 pandemic. Temporary reduction in fossil fuel consumption is one of the factors that led to air quality improvement.
- Wildfires in the United States, Australia, Siberia, and South America in 2020 resulted in major air pollution spikes in these areas.
- The importance of real-time air quality data is highlighted as the report stated that the areas where real-time monitoring remains sparse, leads to low air quality awareness.
Air Pollution in COVID Times – World Air Quality Report Data
Dramatic air quality improvement was witnessed in 2020 due to the emergence of regulations brought in on the account of the COVID-19 pandemic. However, another important observation brought forward by the report was that the group of people who are exposed to long-term air pollution are more susceptible to health impacts led by the SARS-CoV-2 virus. Out of the total deaths due to COVID, between 7% to 33% are attributable to long-term air pollution exposure.
How Air Pollution Exposure leads to Coronavirus Susceptibility?
- Comorbidities – The person that has one or more health conditions could be more exposed to health implications associated with COVID on exposure to chronic air pollution.
- Weakened Lungs and Autoimmune Responses – Cellular inflammation is the effect of particle pollution.
- Increased Virus Susceptibility – According to the report, “Evidence suggests that particle pollution can stimulate a receptor (ACE-2) on cell surfaces and promotes the uptake of the virus.”
- Viral Particle Longevity in the air is associated with greater levels of air pollution.
Did COVID lead to air quality improvement?
Lower industrial and transport emissions were one of the main factors resulting in better air quality. However, to better study the impact of modifications in human behaviours amid pandemic, the report isolated the other main factor, ‘Weather.’ This way, the data that was given reflected the impact of emissions on overall air quality.
- Cities that witnesses the greatest reductions in PM 2.5 levels based on ‘weather corrected’ data 2020, amid the pandemic:
- Cities that witnessed the increase in the PM 2.5 levels amid pandemic:
- São Paulo
- Los Angeles
- Cities that witnessed major impacts on their air quality with lockdowns imposed (PM2.5 levels were almost halved for extended periods of time):
- Los Angeles
Top 10 Most Polluted Countries – World Air Quality Report 2020
The countries that ranked in the top 10 out of 106 countries as the most polluted regions are:
- Bosnia Herzegovina
Which are the countries/regions with the least pollution/PM 2.5 levels?
- Puerto Rico
- New Caledonia
- US Virgin Islands
Most Polluted Capital Cities in 2020
Delhi is the most polluted capital city in the world according to IQAir’s World Air Quality Report 2020. It is followed by:
What is the state of the public monitoring system in countries?
As reported, China, Japan and the United States have the most comprehensive government monitoring networks that publish continuous air quality data.
- African and South American regions lack air quality monitoring systems.
- Lower-income countries lack behind in terms of access to more data availability than high-income countries.
India and World Air Quality Report
32 percent of Indian cities have the ‘Unhealthy’ Air Quality Level in the US Air Quality measurement. Out of 15 most polluted cities in Central and South Asia; 14 cities belong to India. South Asia and Central Asia includes India, Afghanistan, Bangladesh, Iran, Kazakhstan, Kyrgyzstan, Nepal, Pakistan, Sri Lanka, Tajikistan, Turkmenistan and Uzbekistan.
Most polluted and least polluted cities of India:
|Top 5 Most Polluted Indian City||Top 3 Least Polluted Indian City|
In 2020, India showed overall improvements in comparison with 2018 and 2019 performance. The report mentioned India’s National Clean Air Programme (NCAP) having marginal contribution in improving air quality.
The report mentioned stubble burning in India states of Punjab and Haryana which increased 46.5 percent in 2020 from that in 2019.
Challenges faced by India:
- Biomass burning for cooking
- Electricity generation
- Waste burning, and
- Episodic agricultural burning
The World Air Quality Report highlighted the following steps to improve air quality:
- National governments should uptake activities that reduce air pollution emissions.
- Phasing out coal-, gas-, and oil-based energy, as well as waste incinerator facilities
- Promoting and expanding clean energy.
- Transitioning transport to clean energy vehicles
- Improving the infrastructure for cycling and walking.
- Implementation of stringent regulations to curb the menace of air pollution
- Air quality monitoring systems should be expanded either by governments or by NGOs where the latter is supported through funds.
- Participation of all stakeholders at an individual, state and national levels to increase air pollution awareness.
Source: IQAir Official Report