• FIROZ KHAN

      Articles written in Journal of Earth System Science

    • A preliminary assessment of the 7th February 2021 flashflood in lower Dhauli Ganga valley, Central Himalaya, India

      NARESH RANA SHUBHRA SHARMA YASPAL SUNDRIYAL SAMEEKSHA KAUSHIK SUBHENDU PRADHAN GHANSHYAM TIWARI FIROZ KHAN SATI S P NAVIN JUYAL

      More Details Abstract Fulltext PDF

      A short-lived flashflood in Rishi and Dhauli Ganga rivers on 7th February 2021, Uttarakhand Himalaya, killed 65 people with 141 reported missing (official estimate) and devastated two hydropower projects. Geomorphological observations supported by meteorological data suggest that the flood was triggered by a combination of avalanche and debris flow. The Dhauli Ganga valley has preserved ponded sedimentary sequences (laminated sand and silty-clay), suggesting that the valley is prone to episodic mega foods in the recent geological past. Considering that the receding glaciers in the higher Himalaya have left behind enormous sediment, unusual weather events are likely to generate such disasters more frequently as the climate becomes warmer. Thus, the study calls for not only incorporating the disaster risk assessment in the developmental planning of the Himalayan region but also recommends routine monitoring of the potential areas of structural failures in the glaciated valleys along with supra-glacial lakes.

    • Indian summer monsoon variability during the last 20 kyr: Evidence from peat record from the Baspa Valley, northwest Himalaya, India

      FIROZ KHAN NARENDRA KUMAR MEENA YASPAL SUNDRIYAL RAJVEER SHARMA

      More Details Abstract Fulltext PDF

      We present millennial to centennial-scale monsoon variability during the Late-Pleistocene to Holocene using multi-proxy data from 100 cm thick peat deposit in the Baspa Valley, northwest Himalaya. Based on high-resolution mineral magnetism, carbon isotope, and total organic carbon data supported by radiocarbon dating, four climatic phases of alternating strengthened and weakened Indian summer monsoon (ISM) are identified for the last 20 kyr in the higher central Himalaya. Periods of strengthened ISM are dated to ${\sim}$15 to ${\sim}$14 ka, ${\sim}$10 to ${\sim}$7 ka, ${\sim}$2.4 to ${\sim}$1.3 ka, and 243 yr BP to present, which is ascribed to the post-Older Dryas associated with an increase in solar insolation. The phases of weakened ISM are bracketed between ${\sim}$20 and ${\sim}$15 ka, ${\sim}$14 to ${\sim}$10 ka, ${\sim}$7 to ${\sim}$2.4 ka, and ${\sim}$1300 to ${\sim}$243 yr BP. These phases are attributed to global cooling events, i.e., the Last Glacial Maximum (LGM), Younger Dryas (YD), and the Middle to Late Holocene. They govern by changes in the solar insolation.

  • Journal of Earth System Science | News

    • Editorial Note on Continuous Article Publication

      Posted on July 25, 2019

      Click here for Editorial Note on CAP Mode

© 2021-2022 Indian Academy of Sciences, Bengaluru.