Science Snapshots: April 5, 2026

Scientists find one reason why northwest India floods more

Scientists have reported evidence of two subseasonal weather patterns turning northwestern South Asia, including northwest India, from a semiarid region into a flood-prone one. First, the tropical monsoon intra-seasonal oscillation has strengthened and now penetrates deeper inland. Second, the mid-latitude oscillation, a wave of air moving along the jet stream, has slowed, keeping rain-producing systems stuck over the region for longer periods. Together, these changing oscillations account for 44% of the observed increase in flood frequency.

New data explains how black holes have ‘forbidden masses’

The theory of stars predicts that a dying star can’t form a black hole weighing 50 to 130 solar masses, yet gravitational wave observations have detected several black holes in this mass range, puzzling astronomers. By analysing the latest data collected by instruments in Japan, Italy, and the U.S., scientists have now explained this discrepancy as being the result of hierarchical mergers: when two lighter black holes merge to form a heavier one.

‘Chinese researchers account for too many retractions’

Finnish researcher Jonas Oppenlaender analysed 46,087 retractions across 10 major publishers from 1997 to 2026 and found authors affiliated with China accounted for more than 52% of all retractions, a rate roughly 4x higher than China’s actual publication volume. Oppenlaender attributed this to ‘publish or perish’ academic cultures and the rise of paper mills. His analysis also confirmed that each publisher’s own rules determine how much problematic research is actually removed from the public record.