Every year for decades, long rivers of smoke and haze have spread across the Indo-Gangetic Plain in northern India from October to December. That’s when farmers in Punjab, Haryana, Uttar Pradesh, Madhya Pradesh, and other states burn off plant “stubble” after the rice harvest.
When winds are weak and the atmosphere becomes stagnant, the haze can push levels of air pollution several times higher than limits recommended by the World Health Organization. Smoke typically mixes with particles and gases from other sources, such as industry, vehicles, domestic fires (heating and cooking), fireworks, and dust storms, to form the haze, though scientists consider stubble burning to be a major factor.
In some ways, the seasonal timing of stubble fires in 2025 followed typical patterns. Air quality deteriorated in Delhi and several other cities for about a month after crop fires intensified during the last week of October, explained Hiren Jethva, a Morgan State University atmospheric scientist based at NASA’s Goddard Space Flight Center. For about a decade, Jethva has tracked the stubble burning season in India using satellites, and has made predictions about the intensity of the upcoming fire season based on vegetation observations.
The MODIS (Moderate Resolution Imaging Spectroradiometer) on NASA’s Aqua satellite captured this image of a smoky haze darkening skies over much of the plain on November 11, 2025. According to news reports, it was the first of several days in 2025 when pollution levels exceeded 400 on India’s air quality index, the strongest rating on the scale. As in past years, the poor air quality prompted officials in some areas to close schools and institute more stringent air quality controls on construction.
However, the daily timing of burning departs from …