A heavy blanket of smoke filled the air south of the Himalayas in northwest India as dozens of actively burning fires speckled the landscape in northwest India in mid-October 2016. The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Terra satellite captured this true-color image on October 17.
Most of the red hotspots, which mark actively burning fires in this image, cluster in the state of Punjab. Known as India’s “bread basket”, Punjab is a rich agricultural region, growing about 20 percent of wheat produced in India and 10 percent of the rice.
There are two main growing seasons in Punjab: one from May to September and another from November to April. After one crop is finished, many farmers use fire to clear leftover plant debris and ready fields for the next plantings, a practice known as stubble or paddy burning.
The byproduct of the intensive food production and fire-based crop management strategy is smoke. The gray smoke rising from agricultural fires contains particulates and chemical compounds which are respiratory irritants and can damage the health of people and livestock. In some areas of the world the smoke from agricultural fires disperses over a wide area, minimizing the effect in any one locale. In northwest India, however, the tall Himalaya Mountains form a formidable barrier to smoke dispersion, resulting in heavy layers of thick smoke hanging over the valleys south of the mountains. In this image the smoke east of the Punjab region is so thick that the ground is obscured from view.