Decadal changes in two types of the western North Pacific subtropical high in boreal summer associated with Asian summer monsoon/El Niño–Southern Oscillation connections

2010 ◽  
Vol 115 (D21) ◽  
Author(s):  
Jong-Yeon Park ◽  
Jong-Ghap Jhun ◽  
So-Young Yim ◽  
Won-Moo Kim
Keyword(s):  
Summer Monsoon ◽  
North Pacific ◽  
Western North Pacific ◽  
El Nino ◽  
Southern Oscillation ◽  
Asian Summer Monsoon ◽  
Subtropical High ◽  
Boreal Summer ◽  
El Nino Southern Oscillation ◽  
Asian Summer

Enhanced tropospheric biennial oscillation of the East Asian summer monsoon since the late-1970s

2021 ◽  
pp. 1-54
Author(s):  
Wen Chen ◽  
Kaiming Hu ◽  
Shangfeng Chen
Keyword(s):  
Summer Monsoon ◽  
North Pacific ◽  
East Asian Summer Monsoon ◽  
Western North Pacific ◽  
El Nino ◽  
Asian Summer Monsoon ◽  
East Asian ◽  
Tropospheric Biennial Oscillation ◽  
Asian Summer ◽  
Biennial Oscillation

Abstract The tropospheric biennial oscillation (TBO) of East Asian summer monsoon (EASM) has major impacts on East Asian climate. Here it is shown that, since the late-1970s, the TBO signal of EASM has strengthened significantly. The EASM TBO in wind anomalies undergoes a transition from a cyclone over the western North Pacific (WNPC) in preceding summer to an anticyclone over the western North Pacific (WNPAC) in following summer, with the anomalies strengthening remarkably after the late-1970s. Correspondingly, the biennial component of precipitation anomalies in eastern China show different distributions. Both observational and numerical simulation analyses demonstrate that these changes are caused by the westward shift of El Niño warming and enhanced Indo-Pacific and Atlantic-Pacific coupling. The positive sea surface temperature (SST) anomalies associated with the TBO of EASM shift toward the central Pacific after the late-1970s, which favor the strengthening of the WNPC and cause a weakened EASM. In following summer, both the north Indian Ocean and tropical north Atlantic SST warming are closely coupled with El Niño since the late-1970s, which favor the strengthening of WNPAC and cause an intensified EASM. Together, these changes provide more favorable background state for the transition of circulation anomalies over the western North Pacific, giving rise to enhanced biennial variability in EASM in the late-1970s.

scholarly journals Skilful predictions of the Asian summer monsoon one year ahead

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Yuhei Takaya ◽  
Yu Kosaka ◽  
Masahiro Watanabe ◽  
Shuhei Maeda
Keyword(s):  
Long Range ◽  
Summer Monsoon ◽  
Southern Oscillation ◽  
Asian Summer Monsoon ◽  
Boreal Summer ◽  
Climate Modelling ◽  
Large Ensemble ◽  
Asian Society ◽  
Asian Summer ◽  
One Year

AbstractThe interannual variability of the Asian summer monsoon has significant impacts on Asian society. Advances in climate modelling have enabled us to make useful predictions of the seasonal Asian summer monsoon up to approximately half a year ahead, but long-range predictions remain challenging. Here, using a 52-member large ensemble hindcast experiment spanning 1980–2016, we show that a state-of-the-art climate model can predict the Asian summer monsoon and associated summer tropical cyclone activity more than one year ahead. The key to this long-range prediction is successfully simulating El Niño-Southern Oscillation evolution and realistically representing the subsequent atmosphere–ocean response in the Indian Ocean–western North Pacific in the second boreal summer of the prediction. A large ensemble size is also important for achieving a useful prediction skill, with a margin for further improvement by an even larger ensemble.

scholarly journals Global Extratropical Response to Diabatic Heating Variability of the Asian Summer Monsoon

2009 ◽  
Vol 66 (9) ◽  
pp. 2697-2713 ◽  
Author(s):  
Hai Lin
Keyword(s):  
Summer Monsoon ◽  
Indian Summer Monsoon ◽  
North Pacific ◽  
Western North Pacific ◽  
Large Scale ◽  
Asian Summer Monsoon ◽  
Convective Activity ◽  
Mean Flow ◽  
Asian Summer ◽  
Circulation Anomalies

Abstract Global teleconnections associated with the Asian summer monsoon convective activities are investigated based on monthly data of 29 Northern Hemisphere summers defined as June–September (JJAS). Two distinct teleconnection patterns are identified that are associated respectively with variabilities of the Indian summer monsoon and the western North Pacific summer monsoon. The Indian summer monsoon convective activity is associated with a global pattern that has a far-reaching connection in both hemispheres, whereas the western North Pacific summer monsoon convective activity is connected to a Southern Hemisphere wave train that influences the high-latitude South Pacific and South America. A global primitive equation model is utilized to assess the cause of the global circulation anomalies. The model responses to anomalous heatings of both monsoon systems match the general features of the observed circulation anomalies well, and they are mainly controlled by linear processes. The response patterns are largely determined by the summertime large-scale background mean flow and the location of the heating anomaly relative to the upper easterly jet in the monsoon region.

Spring Arctic Oscillation-East Asian summer monsoon connection through circulation changes over the western North Pacific

2011 ◽  
Vol 37 (11-12) ◽  
pp. 2199-2216 ◽  
Author(s):  
Dao-Yi Gong ◽  
Jing Yang ◽  
Seong-Joong Kim ◽  
Yongqi Gao ◽  
Dong Guo ◽  
...  
Keyword(s):  
Summer Monsoon ◽  
North Pacific ◽  
East Asian Summer Monsoon ◽  
Western North Pacific ◽  
Arctic Oscillation ◽  
Asian Summer Monsoon ◽  
East Asian ◽  
Asian Summer ◽  
Circulation Changes

scholarly journals Interannual Seesaw between the Somali and the Australian Cross-Equatorial Flows and its Connection to the East Asian Summer Monsoon

2014 ◽  
Vol 27 (11) ◽  
pp. 3966-3981 ◽  
Author(s):  
Chen Li ◽  
Shuanglin Li
Keyword(s):  
Summer Monsoon ◽  
East Asian Summer Monsoon ◽  
Yellow River ◽  
Southern Oscillation ◽  
Asian Summer Monsoon ◽  
East Asian ◽  
Significant Negative Correlation ◽  
Subtropical High ◽  
Yellow River Valley ◽  
Asian Summer

Abstract The correlations among the summer, low-level, cross-equatorial flows (CEFs) over the Indian–west Pacific Ocean region on the interannual time scale are investigated by using both the NCEP–NCAR reanalysis and 40-yr ECMWF Re-Analysis (ERA-40) datasets. A significant negative correlation (seesaw) has been illustrated between the Somali CEF and the three CEFs north of Australia (the South China Sea, Celebes Sea, and New Guinea; they are referred to in combination as the Australian CEF). A seesaw index is thus defined with a higher (lower) value representing an intensified (weakened) Somali CEF but a weakened (intensified) Australian CEF. The connection of the seesaw with the East Asian summer monsoon (EASM) is then investigated. The results suggest that an enhanced seesaw corresponds to an intensified EASM with more rainfall in north China, the Yellow River valley, and the upper reach of the Yangtze River. The seesaw reflects the opposite covariability between the two atmospheric action centers in the Southern Hemisphere, Mascarene subtropical high, and Australian subtropical high. Whether the seesaw–EASM connection is influenced by El Niño–Southern Oscillation (ENSO) or the Indian Ocean SST dipole mode (IOD) is analyzed. The results remain unchanged when the ENSO- or IOD-related signals are excluded, although ENSO exerts a significant influence. This implies an additional predictability for the EASM from the CEF seesaw.

Sign in / Sign up

Export Citation Format

Share Document