Summary:
- NASA has observed a shift in the timing of stubble burning in northern India, which is impacting air quality in the region.
- Traditionally, farmers would burn crop residues after the harvest, but now they are burning them earlier, leading to increased pollution during the summer months.
- This change in the timing of stubble burning is due to the introduction of new, faster-growing crop varieties, which are being harvested earlier, leading to an earlier burning season.