Details

Autor(en) / Beteiligte

• Ren, Wei
• Tian, Lide
• Shao, Lili

Titel

Regional moisture sources and Indian summer monsoon (ISM) moisture transport from simultaneous monitoring of precipitation isotopes on the southeastern and northeastern Tibetan Plateau

Ist Teil von

• Journal of hydrology (Amsterdam), 2021-10, Vol.601, p.126836, Article 126836

Ort / Verlag

Elsevier B.V

Erscheinungsjahr

2021

Link zum Volltext

Quelle

ScienceDirect

Beschreibungen/Notizen

• •Dates of monsoon onset and retreat on the NETP and SETP were identified.•Convection profoundly affects precipitation isotopes across the ETP.•Moisture sources are distinguishable in isotopic signatures for two study sites.•Rainout and recycling are both important during monsoon moisture transport. The eastern Tibetan Plateau (ETP) is the source region of several large rivers of Asia, and accelerating climate change and enhancing human activity add stress on water availability in that region and downstream. A better understanding of moisture sources to the ETP is critical to anticipate impacts on water resources. An event-based precipitation sampling project for isotopic analysis was carried out in the upstream and end of Indian summer monsoon (ISM) moisture transport pathway across the ETP (at Gongbogvanda on the southeastern TP (SETP) and Madoi on the northeastern TP (NETP)) during the wet season (June-September) 2009, allowing an assessment of moisture sources, and in particular, ISM moisture transport. Combining the time-series of precipitation δ18O, d-excess (d = δ2H-8δ18O) and meteorology, monsoon season was identified to start ~ 3 days later but end ~ 3 days earlier at the NETP site than at the SETP site. Precipitation δ18O demonstrates an amount effect at both the SETP and NETP sites, and this is closely associated with the monsoon activity and related convection precipitation during the monsoon season. Back trajectory analysis reveals moisture to the SETP site is mainly originated from the Bay of Bengal and South Asia, and to the NETP site, an important moisture source from East Asia was identified besides the Bay of Bengal. Further examination reveals characteristic δ18O, d-excess and δ18O-δ2H relations for these moisture sources. Moreover, we roughly evaluated the entrainment of moisture along the ISM moisture transport pathway, and found recycling may contribute to ~ 17–27% of total moisture transported from the SETP to NETP. Our results provide an isotopic insight into moisture sources and ISM moisture transport across the ETP, and would benefit further regional isotope-based climate/hydrological studies.