Breathe easier in the world's most polluted region—the Indo-Gangetic Plain of South Asia, home to Lucknow, India! Our mobile lab zipped through neighborhoods to uncover hidden air pollution patterns. Nearby traffic and factories mix with distant haze, fueling particle growth that worsens smog—especially at night. These insights pinpoint exact hotspots, empowering smarter fixes to clear the air and safeguard families' health in fast-growing cities.

High-time-resolution observations in the Maldives indicate that submicron aerosol over the northern Indian Ocean is primarily composed of inorganic sulfate and highly oxidised organic matter, indicative of aged continental outflow. The consistent composition across various air mass origins, alongside identification of sulfur-containing organics, underscores the influence of long-range transport and sulfate-driven secondary chemistry on regional aerosol characteristics and their climate impacts.

This paper proposes a novel source apportionment paradigm that predicts the relative contributions of different air-pollution sources using a machine-learning framework applied to data obtained from low-cost sensor units. A key strength of this approach is its ability to support a dense network of low-cost sensor units spanning wide geographical areas and providing source apportionment results in real time, thus helping policymakers take regulatory action to curb air pollution in real time.

We used ground-based remote sensing data from the Aerosol Robotic Network to examine long-term trends in aerosol characteristics. We found aerosol loadings generally decreased globally, and aerosols became more scattering. These changes are closely related to variations in aerosol compositions, such as decreased anthropogenic emissions over East Asia, Europe, and North America; increased anthropogenic sources over northern India; and increased dust activity over the Arabian Peninsula.

Our study delves into the elemental composition of aerosols at three sites across the Indo-Gangetic Plain (IGP), revealing distinct patterns during pollution episodes. We found significant increases in chlorine (Cl)-rich and solid fuel combustion (SFC) sources, indicating dynamic emission sources, agricultural burning impacts, and meteorological influences. Surges in Cl-rich particles during cold periods highlight their role in particle growth under high-relative-humidity conditions.