Decadal-Scale Variation of South Asian Summer Monsoon Onset and Its Relationship with the Pacific Decadal Oscillation

Watanabe, Toshiya; Yamazaki, Koji

doi:10.1175/jcli-d-13-00541.1

Cited by 51 publications

(37 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We also display the 30-yr running average of the PDO index to highlight its interdecadal component. We found the same increase in the correlation as reported by Watanabe and Yamazaki (2014) during the early 1970s, with values reaching statistical significance by 1975. This increase is concurrent with the strong upward trend of the 30-yr filtered PDO.…”

Section: B Long-term Relation Of Mok With Enso and Pacific Decadal Osupporting

confidence: 89%

“…5) The recently described relationship between the PDO and MOK limited to the phases characterized by the shift from negative to positive PDO phases has been confirmed for two complete PDO cycles. Watanabe and Yamazaki (2014) postulated that a stationary wave train plays an active role in connecting both the North Pacific Ocean and South Asian monsoon region. Because of the limitation of their study to the period 1948-2011, they suggested that this link should be further addressed by using longer-term data.…”

Section: Summary and Remarksmentioning

confidence: 99%

See 1 more Smart Citation

Tracking the Indian Summer Monsoon Onset Back to the Preinstrument Period

et al. 2016

View full text Add to dashboard Cite

The Indian summer monsoon onset is one of the most expected meteorological events of the world, affecting the lives of hundreds of millions of people. The India Meteorological Department has dated the monsoon onset since 1901, but its original methodology was considered subjective and it was updated in 2006. Unfortunately, the new method relies on OLR measurements, which impedes the construction of an objective onset series before the 1970s. An alternative approach is the use of the wind field, but the development of such an index is limited to the period covered by reanalysis products. In this paper historical wind records taken on board ships are used to develop a new onset series using only wind direction measurements, providing an objective record of the onset since the late nineteenth century. The new series captures the rapid precipitation increase associated with the onset, correlates well with previous approaches, and is robust against anomalous (bogus) onsets. A tendency for later-than-average onsets during the 1900-25 and 1970-90 periods and earlier-than-average onsets between 1940 and 1965 was found. A relatively stable relationship between ENSO and Indian monsoon onset dates was found; however, this link tends to be weaker during decades characterized by prevalent La Niña conditions. Furthermore, it was found that the link between the Pacific decadal oscillation (PDO) and the onset date is limited to the phases characterized by a shift from negative to positive PDO phases.

show abstract

Section: B Long-term Relation Of Mok With Enso and Pacific Decadal Osupporting

confidence: 89%

Section: Summary and Remarksmentioning

confidence: 99%

Tracking the Indian Summer Monsoon Onset Back to the Preinstrument Period

et al. 2016

View full text Add to dashboard Cite

show abstract

“…The dynamics linking the ASM onset and interdecadal variability of the Pacific have been well addressed in previous works [ Kajikawa and Wang , ; Kajikawa et al ., ; Xiang and Wang , ; Watanabe and Yamazaki , ]. The direct driver of the earlier onset of the ASM is the earlier overturning of the meridional heat contrast between the Asian continent and the Indian Ocean in the premonsoon season.…”

Section: Mechanisms For the Wetting Trend Over The Tpmentioning

confidence: 99%

“…Xiang and Wang [] document the decadal shift in the Pacific basin to a “grand” La Niña‐like pattern in the 1990s in driving the earlier onset of the ASM since the late 1970s through the westward emanation of Rossby waves, based on numerical experiments. Watanabe and Yamazaki [] demonstrate that the negative Pacific Decadal Oscillation phase in recent decades is important for the earlier overturning of the meridional heat contrast in the ASM region via exciting a stationary wave train from the northern Pacific Ocean to central Asia.…”

Section: Mechanisms For the Wetting Trend Over The Tpmentioning

confidence: 99%

Wetting and greening Tibetan Plateau in early summer in recent decades

2017

View full text Add to dashboard Cite

The Tibetan Plateau (TP) plays an essential role in the global hydrological cycle. Unlike the well‐recognized surface warming, changes in precipitation over the TP and the underlying mechanisms remain ambiguous. A significant increase in the amount of precipitation over the southeastern TP in May over 1979–2014 (13.46% decade−1 of the climatology) is identified in this study, based on homogenized daily rain gauge data. Both the increased precipitation frequency and intensity have contributions. The coherent increases in soil moisture content and vegetation activities further confirm the precipitation trend, indicating a wetting and greening TP in the early summer in recent decades. The moisture budget analysis shows that this wetting trend in the past four decades is dominated by the increased water vapor convergence due to circulation changes, while increases in specific humidity play a minor role. The wetting trend over the TP in May results directly from the earlier onset of the South Asian summer monsoon (ASM) since the late 1970s associated with the phase transition of Interdecadal Pacific Oscillation around the late 1990s. The earlier onset of the ASM triggers low‐level southwesterly anomalies over the northern Indian Ocean, promoting moisture convergence and increased precipitation over the TP in May. Specifically, the increased amount of precipitation after the onset of the ASM explains 95% of the increase in the total amount of precipitation in May.

show abstract

“…Krishnamurthy and Krishnamurthy (2013) showed that the warm (cold) phase of the PDO is associated with a deficit (excess) of rainfall over India in June-September. Recently, Watanabe and Yamazaki (2014) further found that the early onset of summer monsoon in Kerala, considered as the beginning of India's rainy season by many studies (e.g. Wang et al, 2009a), is closely associated with the negative PDO through the teleconnection of the stationary wave train, thus intensifying the land-sea thermal contrast.…”

Section: Onset Of the Asian Summer Monsoonmentioning

confidence: 98%

From MONEX to the global monsoon: A review of monsoon system research

et al. 2014

View full text Add to dashboard Cite

Substantial progress has been made over the past three decades since the Monsoon Experiments (MONEX) of 1978-79. Here, we review these achievements by highlighting four breakthroughs in monsoon research: (1) The identification of the coupled ocean-land-atmosphere nature of the monsoon in the process of the annual cycle of solar heating; (2) new understanding of the changes in the driving forces of monsoon systems, with anthropogenic factors (climate effects of increased greenhouse gas and aerosol emissions) playing an important role in the regulation of monsoons; (3) detection of the interdecadal-and centennial-scale variability of monsoon systems, and its attribution to the combined impact of global warming and natural (especially oceanic) effects; and (4) the emerging concept of the global monsoon and its long-term variation under the impact of global climate change. All the observational and model-derived evidence demonstrates that the monsoon system, as an important component of the global climate system, has already changed and will continue to change in the future. This picture of an evolving monsoon system poses great challenges for near-term prediction and long-term projection.

show abstract

Decadal-Scale Variation of South Asian Summer Monsoon Onset and Its Relationship with the Pacific Decadal Oscillation

Cited by 51 publications

References 27 publications

Tracking the Indian Summer Monsoon Onset Back to the Preinstrument Period

Tracking the Indian Summer Monsoon Onset Back to the Preinstrument Period

Wetting and greening Tibetan Plateau in early summer in recent decades

From MONEX to the global monsoon: A review of monsoon system research

Contact Info

Product

Resources

About