AUTHOR=Vishwakarma Bramha Dutt , Ramsankaran RAAJ , Azam Mohd. Farooq , Bolch Tobias , Mandal Arindan , Srivastava Smriti , Kumar Pankaj , Sahu Rakesh , Navinkumar Perumal Jayaraman , Tanniru Srinivasa Rao , Javed Aaquib , Soheb Mohd , Dimri A. P. , Yadav Mohit , Devaraju Balaji , Chinnasamy Pennan , Reddy Manne Janga , Murugesan Geetha Priya , Arora Manohar , Jain Sharad K. , Ojha C. S. P. , Harrison Stephan , Bamber Jonathan TITLE=Challenges in Understanding the Variability of the Cryosphere in the Himalaya and Its Impact on Regional Water Resources JOURNAL=Frontiers in Water VOLUME=Volume 4 - 2022 YEAR=2022 URL=https://www.frontiersin.org/journals/water/articles/10.3389/frwa.2022.909246 DOI=10.3389/frwa.2022.909246 ISSN=2624-9375 ABSTRACT=

The Himalaya plays a vital role in regulating the freshwater availability for nearly a billion people living in the Indus, Ganga, and Brahmaputra River basins. Due to climate change and constantly evolving human-hydrosphere interactions, including land use/cover changes, groundwater extraction, reservoir or dam construction, water availability has undergone significant change, and is expected to change further in the future. Therefore, understanding the spatiotemporal evolution of the hydrological cycle over the Himalaya and its river basins has been one of the most critical exercises toward ensuring regional water security. However, due to the lack of extensive in-situ measurements, complex hydro-climatic environment, and limited collaborative efforts, large gaps in our understanding exist. Moreover, there are several significant issues with available studies, such as lack of consistent hydro-meteorological datasets, very few attempts at integrating different data types, limited spatiotemporal sampling of hydro-meteorological measurements, lack of open access to in-situ datasets, poorly accounted anthropogenic climate feedbacks, and limited understanding of the hydro-meteorological drivers over the region. These factors result in large uncertainties in our estimates of current and future water availability over the Himalaya, which constraints the development of sustainable water management strategies for its river catchments hampering our preparedness for the current and future changes in hydro-climate. To address these issues, a partnership development workshop entitled “Water sEcurity assessment in rIvers oriGinating from Himalaya (WEIGH),” was conducted between the 07th and 11th September 2020. Based on the intense discussions and deliberations among the participants, the most important and urgent research questions were identified. This white paper synthesizes the current understanding, highlights, and the most significant research gaps and research priorities for studying water availability in the Himalaya.