Abstract

The future changes in runoff of Himalayan glacierised catchments will be determined by the local climate forcing and the climate sensitivity of the runoff. Here, we investigate the sensitivity of summer runoff to precipitation and temperature changes in winter-snow dominated Chandra (the western Himalaya) and summer-rain dominated upper Dudhkoshi (the eastern Himalaya) catchments. We analyse the interannual variability of summer runoff in these catchments during 1980–2018 using a semi-distributed glacio-hydrological model, which is calibrated with the available runoff and glacier mass balance observations. Our results indicate that despite the contrasting precipitation regimes, the catchments have a similar runoff response: The summer runoff from the glacierised parts of both the catchments is sensitive to temperature changes and is insensitive to precipitation changes; the summer runoff from the non-glacierised parts has an exactly opposite pattern of sensitivity for both the catchments. The precipitation-independent glacier contribution stabilises the catchment runoff against precipitation variability to some degree. The estimated sensitivities capture the characteristic ‘peak water’ in the long-term mean summer runoff, which is caused by the excess meltwater released by the shrinking ice reserve. As the glacier cover depletes, the summer runoff is expected to become more sensitive to precipitation forcing in these catchments. However, The net impact of the glacier loss on the catchment runoff may not be detectable, given the relatively large interannual runoff variability in these catchments.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.