Analysis of Seasonal Pollutant Changes and Air Quality in New Delhi

May 5, 2026, 21:48
AsiaEnvironment

Introduction

Recent data and atmospheric observations show that air quality in New Delhi is influenced by specific seasonal cycles for different pollutants, rather than one single trend.

Main Body

Research by Envirocatalysts, using data from the Central Pollution Control Board, shows that different pollutants follow different patterns throughout the year. For example, particulate matter (PM2.5 and PM10) reaches its highest levels during winter, from October to February. In contrast, nitrogen dioxide (NO2) and ozone (O3) are more concentrated during the summer, with ozone peaking in May due to sunlight reacting with nitrogen oxides. Furthermore, the decrease in particulate matter during the middle of the year is caused by rain and wind rather than a reduction in actual emissions. Experts emphasize that the city needs a more detailed approach to reduce pollution. Sunil Dahiya from Envirocatalysts asserted that relying on weather conditions to clear the air is not enough; instead, the government should target the sources of emissions. He highlighted that PM2.5, CO, and NO2 mainly come from industrial and transport combustion, whereas PM10 is mostly caused by dust and construction work. Recent observations support these findings. In May, air quality briefly improved to 'satisfactory' levels because of rain and wind. During this time, ozone became the main pollutant, which confirms the seasonal shift from particles in winter to gases in the pre-monsoon period. However, forecasts suggest that air quality will return to 'moderate' or 'poor' levels as these weather effects fade.

Conclusion

Air quality in New Delhi has improved briefly due to the weather, but long-term data shows that the city still needs specific strategies to target different types of pollutants.

Learning

πŸŒ‰ The 'Bridge' Concept: Moving from Simple to Complex Connections

At the A2 level, you likely use simple words like and, but, and so. To reach B2, you need to use Contrast and Cause Markers to show how ideas relate to each other. This article is a goldmine for this transition.

πŸ”„ The Power of 'In Contrast' vs. 'However'

Look at how the author separates two different groups of pollutants:

"...PM2.5 and PM10 reaches its highest levels during winter... In contrast, nitrogen dioxide (NO2) and ozone (O3) are more concentrated during the summer."

The B2 Upgrade: Instead of saying "Winter is bad, but summer is also bad," use "In contrast" to highlight a direct opposite. It signals to the reader that you are comparing two different categories.

πŸ› οΈ Causal Logic: 'Due to' and 'Rather than'

B2 speakers don't just say "because." They vary their language to explain why things happen.

  1. Due to (Replacement for 'because of'):

    • Example: "...ozone peaking in May due to sunlight reacting..."
    • Usage: Use this before a noun phrase to sound more professional and academic.

  2. Rather than (The 'Correction' tool):

    • Example: "...caused by rain and wind rather than a reduction in actual emissions."
    • Usage: This is a high-level way to say "not this, but that." It shows you can analyze a situation and reject a wrong idea.

✍️ Vocabulary Shift: The 'Action' Verbs

Stop using say for everything. Notice how the article describes the experts:

  • Asserted: (Stronger than 'said' β†’\rightarrow implies a confident statement of fact).
  • Highlighted: (Better than 'showed' β†’\rightarrow implies bringing attention to a specific point).
  • Confirms: (Better than 'proves' β†’\rightarrow implies that new data matches an old theory).

Quick Guide for your next writing:

  • ❌ But β†’\rightarrow βœ… However / In contrast
  • ❌ Because β†’\rightarrow βœ… Due to / Since
  • ❌ Said β†’\rightarrow βœ… Asserted / Highlighted

Vocabulary Learning

analysis
An examination of data or information to understand it better
Example:The analysis of the data revealed clear patterns in pollution levels.
pollutant
A substance that makes air or water dirty or harmful
Example:Particulate matter is a common pollutant in cities.
seasonal
Relating to a particular season of the year
Example:Seasonal changes affect the levels of ozone.
air quality
The cleanliness or pollution level of the air
Example:Improving air quality is a priority for the city.
influenced
Affected or shaped by something else
Example:Air quality is influenced by weather conditions.
specific
Clearly defined or particular
Example:The report highlighted specific pollutants that need attention.
cycles
Repeated patterns or sequences over time
Example:The pollution cycles repeat every year.
patterns
Regular arrangements or trends that can be observed
Example:Scientists study pollution patterns to predict future levels.
particulate matter
Tiny solid or liquid particles suspended in the air
Example:Particulate matter can cause breathing problems.
highest levels
The greatest amount or concentration of something
Example:The city reaches its highest levels of pollution in winter.
winter
The cold season of the year
Example:Winter brings colder temperatures and higher pollution.
summer
The hot season of the year
Example:Summer often sees increased ozone levels.
ozone
A gas that protects the Earth from harmful ultraviolet light, but at ground level can be harmful
Example:Ozone at ground level is harmful to health.
sunlight
Light that comes from the sun
Example:Sunlight triggers chemical reactions that form ozone.
reacting
Changing when combined with another substance
Example:Ozone reacts with nitrogen oxides to form pollutants.
nitrogen oxides
Gases made of nitrogen and oxygen that are emitted by combustion engines
Example:Nitrogen oxides are emitted by vehicle engines.
decrease
To become smaller or less in amount
Example:The decrease in particulate matter was due to rainfall.
rain
Water falling from clouds in droplets
Example:Rain helps to wash away pollutants from the air.
wind
Moving air that can transport particles
Example:Wind can disperse air pollution over large areas.
emissions
Gases or particles released into the air
Example:Reducing emissions is essential for cleaner air.
emphasis
Special importance or focus given to something
Example:The study placed emphasis on industrial sources.
approach
A way of doing something or a method
Example:A new approach is needed to tackle air pollution.
reduce
To make something smaller or less
Example:We must reduce emissions to improve air quality.
rely
To depend on something for support or help
Example:Relying on weather alone is not enough to clear the air.
conditions
Circumstances or factors that exist at a particular time
Example:Weather conditions can affect pollution levels.
clear
To make free from dirt or pollution
Example:The goal is to clear the air of harmful particles.
target
To aim at or focus on something specific
Example:The government should target the main sources of pollution.
sources
Origins or places where something comes from
Example:Identifying sources helps in controlling pollution.
industrial
Relating to factories or manufacturing
Example:Industrial activities contribute significantly to emissions.
transport
Movement of people or goods from one place to another
Example:Transport emissions are a major source of NOβ‚‚.
combustion
The process of burning that releases heat and gases
Example:Combustion of fossil fuels releases COβ‚‚.
construction
The act of building or erecting structures
Example:Construction sites generate dust and particulate matter.
observations
Notices or records of what has been seen or measured
Example:Observations confirm the seasonal shift in pollutants.
briefly
For a short period of time
Example:The air quality improved briefly after the rain.
improved
Became better or more satisfactory
Example:The air quality improved thanks to the rainfall.
satisfactory
Good enough to meet a requirement or expectation
Example:The conditions became satisfactory after the storm.
forecast
A prediction about future events or conditions
Example:The forecast predicts a return to moderate pollution.
moderate
Of average or middle level, not extreme
Example:Moderate pollution levels are still harmful.
poor
Bad or low quality
Example:Poor air quality can lead to health problems.
long-term
Spanning or lasting for a long period of time
Example:Long-term data shows persistent pollution issues.
strategies
Planned methods or actions to achieve a goal
Example:Effective strategies are needed to reduce pollution.
nitrogen dioxide
A gas that irritates the lungs and is emitted by vehicles
Example:Nitrogen dioxide is a harmful pollutant emitted by cars.