Impact of Northwest Pacific anticyclone on the Indian summer monsoon region

• Published in: Theoretical and applied climatology Vol. 113; no. 1-2; pp. 329 - 336
• Main Authors: Chowdary, J. S., Gnanaseelan, C., Chakravorty, Soumi
• Format: Journal Article
• Language: English
• Published: Vienna Springer Vienna 01.07.2013; Springer; Springer Nature B.V
• Subjects: Aquatic Pollution; Atmospheric circulation; Atmospheric Protection/Air Quality Control/Air Pollution; Atmospheric Sciences; Climatology; Climatology. Bioclimatology. Climate change; Earth and Environmental Science; Earth Sciences; Earth, ocean, space; Environmental impact; Exact sciences and technology; External geophysics; Marine; Meteorology; Monsoons; Ocean basins; Ocean warming; Original Paper; Rain and rainfall; Southern oscillation; Summer; Tidal waves; Troposphere; Waste Water Technology; Water Management; Water Pollution Control; Indian Ocean; Asia; Bay of Bengal; Pacific Ocean; Northwest Pacific; North Pacific; India; ISW, Indian Ocean Basin; INW, Pacific; I, Pacific; IW, Pacific; ISW, Bangladesh, Bengal Bay; Tropical Indian Ocean; Indian Summer Monsoon Rainfall; Maritime Continent; North Indian Ocean; Indian Summer Monsoon; rainfall; Anticyclone; atmospheric precipitation; Sea level pressure; ocean-atmosphere interaction; Summer monsoon; Interannual variation
• ISSN: 0177-798X; 1434-4483
• DOI: 10.1007/s00704-012-0785-9

Influence of northwest (NW) Pacific anticyclone on the Indian summer monsoon (ISM), particularly over the head Bay of Bengal and monsoon trough region, is investigated. Strong NW Pacific anticyclone during summer induces negative precipitation anomalies over the head Bay of Bengal and Gangetic Plain region. Westward extension of moisture divergence and dry moisture transport from NW Pacific associated with anticyclone (ridge) and local Hadley cell-induced subsidence are responsible for these negative precipitation anomalies. The impact is maximum when the anticyclone and Indian Ocean basin warming co-occur. This contributes significantly to year-to-year variability of ISM.