Spatial and meteorological controls of stable water isotope dynamics of precipitation in Kashmir Valley, Western Himalaya, India

ABSTRACT

In the Himalayas, the lives and livelihoods of millions of people are sustained by water resources primarily depending on the moisture brought by Western Disturbances and Indian Summer Monsoon. In the present study, a network of 12 precipitation stations was established across the Kashmir Valley to understand the spatial and meteorological factors controlling precipitation isotopes. Temperature and relative humidity are dominant meteorological factors, whereas altitude, proximity to forest canopy, land use/land cover, windward and leeward sides of the mountains are the main physical factors influencing precipitation isotopes. The study suggests that the Mediterranean Sea and nearby water bodies along with continental recycling are the dominant sources of moisture from October to May, while the Arabian Sea, Bay of Bengal and continental recycling are the main sources of moisture from June to September. However, some precipitation events from October to May collect moisture from the Arabian Sea and some precipitation events from June to September collect moisture from the Mediterranean Sea. The occasional passage of Western Disturbances in summer merging with the Indian Summer Monsoon yields heavy to very heavy precipitation. The study provides a better understanding of complex spatial and meteorological phenomena controlling precipitation isotopes across the Western Himalayas.

KEYWORDS:

• D-excess
• Himalaya
• hydrogen-2
• isotope hydrology
• oxygen-18
• precipitation
• physiography
• recycling

Acknowledgements

The authors gratefully acknowledge the NOAA Air Resource Laboratory (ARL) for the open source facility of the HYSPLIT model and NCEP/NCAR Reanalysis data used in this publication. The meteorological data procured from IMD Srinagar are also duly acknowledged. We are also highly thankful to the reviewers for their constructive comments and suggestions, which improved the quality of the manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The work was financially supported by the Ministry of Earth Sciences (GoI) under research project no: MoES/PAMC/H&C/92/2016-PCII.