Impact of Northwest Pacific anticyclone on the Indian summer monsoon region

Seasonal Prediction of Distinct Climate Anomalies in Summer 2010 over the Tropical Indian Ocean and South Asia

“…7a and 8a). The SST warming over the eastern equatorial Indian Ocean, together with the northwestern Pacific anticyclonic circulation, exerts a strong impact on the rainfall over the head Bay of Bengal and over monsoon trough region (Chowdary et al 2013). Figure 7b shows weak SST anomalies (slightly cooling) off Sumatra and Java in the MME in contrast to the observations.…”

“…8a). The weak monsoon circulation (low-level winds) is not necessarily representing monsoonal convective strength (Izumo et al 2008;Chowdary et al 2013). The weakening of low-level winds sustains the north Indian Ocean warming during JJA 2010, increasing the monsoon rainfall by reducing moist stability and increasing horizontal moisture advection (Yang et al 2007.…”

“…The MME is also able to predict the northwestward tilting of positive SLP anomalies during summer 2010. Studies such as Chowdary et al (2013) indicate that the westward extension of moisture divergence from the SLP ridge is responsible for low rainfall over the head Bay of Bengal region. Strong positive precipitation anomalies over the northwestern parts of South Asia including Pakistan are one of the distinct features observed in summer 2010.…”

Linkages between the South and East Asian summer monsoons: a review and revisit

“…Jin and Chen (1982) suggested that the EAM system significantly affects the SAM system, and that the SAM does not significantly affect the EAM system. Chowdary et al (2013) and Bandgar et al (2014) also suggested that the WNPSH influences the SAM. By using an index to quantify the interface between the SAM and EAM, Cao et al (2012) found that the WNPSH as a major factor for the EAM variability, plays an important role in the negative relationship between the SAM and EAM.…”

“…Zhang (1999Zhang ( , 2001 claimed that the impact of the SAM on the rainfall over North China is through the transportation of water vapor from the Indian region. The Key mechanisms on the connection proposed are (1) the east-west shift of the South Asian High (SAH) (Tao and Zhu 1964;Wei et al 2014), (2) modulation by the WNPSM (Cao et al 2012;Chowdary et al 2013;Bandgar et al 2014), and (3) a mid-latitude circulation pattern over the Asian continent (Krishnan and Sugi 2001;Wu 2002;Wu et al 2003;Greatbatch et al 2013). The SAM tends to affect the EAM via the east-west shift of the SAH exhibiting the tripolar pattern of the summer rainfall anomalies over China (Wei et al 2014).…”