Global warming disrupting Indian-Pacific climate link

A new study has found that major volcanic eruptions can temporarily disrupt the climate connection between the tropical Indian and Pacific oceans, while human-caused global warming may now be driving an unusually severe breakdown in that relationship.

Researchers at the Woods Hole Oceanographic Institution (WHOI) combined paleoclimate evidence with climate model simulations to examine how closely the two ocean basins have behaved over several centuries.

The study found that between 1810 and 1850, the relationship between the two basins changed significantly. Researchers linked the disruption to a series of major tropical volcanic eruptions, which appear to have weakened the Pacific Ocean’s usual influence on climate conditions in the Indian Ocean.

The strength of the disruption depended on both the size of the eruptions and the background climate conditions at the time.

Since the 1980s, however, scientists have observed another weakening of the relationship. The Indian Ocean has increasingly behaved differently from what would normally be expected from conditions in the Pacific, a shift researchers have linked to climate warming.