Writer
Saurabh Dhakad
PhD scholar, Atmospheric Chemistry and Climate Change Lab, School of Environmental Sciences, Jawaharlal Nehru University
Stories by Saurabh Dhakad
The Criteria PollutantsThe twelve pollutants for which India sets national air quality limits, what each one is, where it comes from and what it does.30 Oct 2026 · EducationThe Boundary Layer Lid: Reading Winter Smog Through Potential TemperatureSmoke and gases live mostly in the lowest kilometre of air, the planetary boundary layer. Its potential temperature profile tells us how deep that layer is and how a chimney plume will behave.30 Oct 2026 · Chemistry ExplainedHow the Air Breathes: The Daily Boundary LayerThe layer of air we live in is not fixed. It grows deep by afternoon and shrinks to a thin skin at night, and that daily rhythm decides how dirty our air feels.28 Oct 2026 · Chemistry ExplainedWhy is Delhi’s smog different from LA’s?Los Angeles, Beijing and Delhi are all famous for smog, but each city cooks its haze from a different recipe of fuel, sunlight and weather. Seeing the difference tells us where Delhi’s winter air really comes from.27 Oct 2026 · Air & SocietyThe Layers of the Atmosphere: Why Temperature Keeps Turning AroundFrom the smoggy air at our doorstep to the edge of space, the atmosphere is stacked in layers. Each one has its own source of heat, and that decides whether it gets warmer or colder as we climb.27 Oct 2026 · Chemistry Explainedppb or µg/m³? Reading air pollution unitsAir quality numbers come in counts, in weights and in index points. A simple formula links the first two, and knowing the third explains why apps rarely agree.26 Oct 2026 · Data & MethodsFive molecules that run the lower atmosphereOzone, OH, HO₂, NO and NO₂ are few in number but do most of the chemistry in the air we breathe. Here is who they are and how they work together.25 Oct 2026 · Chemistry ExplainedEven Clean Air Is Full of ChemistryThe air over a quiet ocean or a deep forest looks empty, but it is busy with sulphur from plankton, gases from leaves and a fast cleaning molecule made by sunlight.23 Oct 2026 · Chemistry ExplainedA Tale of Two Smogs: London 1952 and Los AngelesBoth cities gave the world the word ‘smog’, but the air in each was made by very different chemistry. Knowing the difference helps us read our own winter haze.20 Oct 2026 · Chemistry ExplainedPrimary vs Secondary PollutantsWhich pollutants come straight out of a source, which ones form in the air from other gases, and why the difference decides how we control them.19 Oct 2026 · EducationFires After Three: Why Satellites Are Missing Punjab’s Farm FiresFarm fire counts are rising again this October. But the satellites that count them pass overhead before most fires are lit, so the real picture is bigger than the numbers we see.19 Oct 2026 · Data & MethodsClean-Air Money: Why Most of It Went to Dust, and What Needs More AttentionEight months after the budget, winter is here again. Two-thirds of India’s clean-air money has gone into controlling road dust. Here is why, what the science says about how well it works, and where more attention could help.17 Oct 2026 · Air & PolicyNatural vs anthropogenic sourcesWhat nature puts into the air, what people put into it, and the cases where the line between the two is easy to get wrong.16 Oct 2026 · EducationPhotolysis: How Sunlight Breaks Molecules ApartEvery morning, sunlight starts pulling molecules in the air apart. This quiet demolition builds the ozone layer, cooks up city smog and keeps the air clean.16 Oct 2026 · Chemistry ExplainedSame air, different number: why India’s AQI and the US AQI disagreeOn the same morning in Delhi, one app says the air is “Moderate” and another says “Unhealthy”. Neither is wrong. They are reading the same air through different rulebooks.14 Oct 2026 · Air & SocietyThe atmosphere’s detergent: the radical that cleans our airA radical that lives for less than a second removes most of the pollution we put into the sky. It runs on sunlight, so in Delhi’s hazy winter the cleaning slows down.13 Oct 2026 · Chemistry ExplainedGRAP 2026: What’s New, and Will It Actually Clear Delhi’s Air?Delhi’s winter emergency plan has been tightened again. Diesel generator and bus rules now start at the first stage, and more construction sites are watched for dust. But the chemistry of smog works on a slower clock than the plan does.12 Oct 2026 · Air & PolicyBreathing plastic: microplastics in the air we inhaleWe worry about plastic in the oceans. But tiny plastic fibres also float in the air of our homes and cities, and scientists have now found them deep inside human lungs.11 Oct 2026 · Air Pollution & HealthHow do we know the smoke came from the fields?Every October-November, Delhi argues over how much of its smog comes from crop burning in Punjab and Haryana. Chemists don’t guess. They read the smoke’s fingerprints.10 Oct 2026 · Chemistry ExplainedFrom raindrop to data: how we analyse rainwaterA rain sample is easy to collect and easy to ruin. Here’s how scientists turn a bottle of rainwater into a reliable record of the air.9 Oct 2026 · Data & MethodsWhat's in the rain? The chemistry of a Delhi monsoon showerRain looks like the cleanest water there is. By the time it reaches the ground, it has scrubbed the air on the way down, and its chemistry tells us what we've been breathing.8 Oct 2026 · Chemistry ExplainedWhat's inside Delhi’s particulate matter?We talk about PM2.5 as if it were one thing. Under the microscope, each tiny particle is a mixture, and most of it wasn't emitted as a particle at all.7 Oct 2026 · Chemistry ExplainedWhy I am starting VayuVartaA researcher's reasons for writing about the air in public, and what to expect from this blog.6 Oct 2026 · Air & SocietyWhy Delhi's air turns toxic every winter: the chemistry behind the smogIt isn't only that we pollute more in winter. The cold, still air turns gases into particles and traps them close to the ground.6 Oct 2026 · Chemistry Explained