This research paper investigates the predictability of Indian Summer Monsoon Rainfall (ISMR) by exploring the causal relationship between North Atlantic sea-surface temperature (NA-SST) and ISMR. Using nonlinear causal inference techniques, the study establishes that NA-SST and El Niño-Southern Oscillation (ENSO) are independent drivers of ISMR, with NA-SST contributing as much to ISMR variability as ENSO. The findings support a teleconnection mechanism where NA-SST influences ISMR through Rossby wave trains, modulating active and break spells of monsoon rainfall.

B. N. Goswami, Deepayan Chakraborty, P. V. Rajesh, Adway Mitra