Short-term variability in the dates of the Indian monsoon onset and retreat on the southern and northern slopes of the central Himalayas as determined by precipitation stable isotopes
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This project launched the first study to compare the stable isotopes (δ18O and δD) in daily precipitation at Kathmandu (located on the southern slope of the central Himalayas) and Tingri (located on the northern slope). The results show that low δ18O and δD values of summer precipitation at the two stations were closely related to intense convection of the Indian monsoon. However, summer δ18O and δD values at Tingri were lower than those at Kathmandu, a result of the lift effect of the Himalayas, coupled with convection disturbances and lower temperatures at Tingri. In winter, the relatively high δ18O and δD values at the two stations appears to have resulted from the influence of the westerlies. Compared with those during the summer, the subsidence of the westerlies and northerly winds resulted in relatively high δ18O and δD values of the winter precipitation at Tingri. Winter δ18O and δD values at Kathmandu far exceeded those at Tingri, due to more intense advection of the southern branch of the westerlies, and higher temperatures and relative humidity at Kathmandu. The detailed differences in stable isotopes between the two stations follow short-term variability in the onset date of the Indian monsoon and its retreat across the central Himalayas. During the sampling period, the Indian monsoon onset at Tingri occurred approximately 1 week later than that at Kathmandu. However, the retreat at Tingri began roughly 3 days earlier. Clearly, the duration of the Indian monsoon effects last longer at Kathmandu than that at Tingri. Our findings also indicate that the India monsoon travels slowly northward across the central Himalayas due to the blocking of the Himalayas, but retreats quickly.
KeywordsPrecipitation Stable isotopes Indian monsoon Central Himalayas
This work was jointly supported by the Major Program of the National Natural Science Foundation of China (Grant No. 41190081), the Strategic Priority Research Program of Chinese Academy of Sciences (Grant No. XDB03030207) and the National Natural Science Foundation of China (Grant Nos. 91437110, 41371086, and 41125003). The authors gratefully acknowledge the NOAA Air Resources Laboratory (ARL) for the provision of the HYSPLIT transport model (http://ready.arl.noaa.gov/HYSPLIT.php) used in this publication. NOAA/OAR/ESRL PSD, Boulder, Colorado, USA, provided NCEP reanalysis-derived data, via their website: http://www.esrl.noaa.gov/psd/.
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Conflict of interest
The authors declare that they have no conflicts of interest.
- Clark I, Fritz P (1997) Environmental isotopes in hydrogeology. Lewis Publishers, Boca Raton, New York, p 47Google Scholar
- Gao D, Zou H, Wang W (1985) Influence of water vapor pass along the Yarlungzangbo River on precipitation (in Chinese with English abstract). Mount Res 3(4):239–249Google Scholar
- Kurita N (2013) Water isotopic variability in response to mesoscale convective system over the tropical ocean. J Geophys Res 118:10376–10390Google Scholar
- Lin Z, Wu X (1990) A preliminary analysis about the tracks of moisture transportation on the Qinghai-Xizang Plateau (in Chinese with English abstract). Geogr Res 9(3):30–49Google Scholar
- Managave SR, Jani RA, Rao TN, Khadgarai S, Ramesh R (2014) Intra-event isotope and drop size data reveal post-condensation effects in tropical rain. American Geophysical Union, Fall Meeting, abstract #PP31D-1161Google Scholar
- Murakami T (1987) Effect of the Tibetan Plateau. In: Chang CP, Krishnamurti TN (eds) Monsoon meteorology. Oxford University Press, New York, pp 235–270Google Scholar
- Pai DS, Bhan SC (2013) Monsoon 2012: a report (IMD Met. monograph: synoptic meteorology no. 13/2013). India Meteorological Department, National Climate Center, Pune, IndiaGoogle Scholar
- Pai DS, Bhan SC (2014) Monsoon 2013: a report (IMD Met. monograph no: ESSO/IMD/SYNOPTIC MET/01-2014/15). India Meteorological Department, National Climate Center, Pune, IndiaGoogle Scholar
- Rozanski K, Araguás-Araguás L, Gonfiantini R (1993) Isotopic patterns in modern global precipitation. In: Swart PK, Lohmann KC, McKenzie J, Savin S (eds) Climate change in continental isotopic records geophysical monograph 78. American Geophysical Union, Washington, DC, pp 1–36CrossRefGoogle Scholar
- Tyagi A, Pai DS (2012) Monsoon 2011: a report (IMD Met. monograph: synoptic meteorology no. 01/2012). India Meteorological Department, National Climate Center, Pune, IndiaGoogle Scholar
- Wushiki H (1977) Deuterium content in the Himalayan precipitation at Khumbu District, observed in 1974/1975. Seppyo 39:50–56Google Scholar
- Yang Y, Gao D, Li B (1987) The preliminary results of studying water vapor pass along the downstream of Yarlung Zangbo (in Chinese). Sci China Ser B 8:893–902Google Scholar
- Yao T, Masson-Delmotte V, Gao J, Yu W, Yang X, Risi C, Sturm C, Werner M, Zhao H, He Y, Ren W, Tian L, Shi C, Hou S (2013) A review of climatic controls on δ18O in precipitation over the Tibetan Plateau: observations and simulations. Rev Geophys 51:525–548. doi: 10.1002/rog.20023 CrossRefGoogle Scholar