Water vapour characteristics and radiative effects at high-altitude Himalayan sites

U. C. Dumka, D. G. Kaskaoutis, Pradeep Khatri, Shantikumar S. Ningombam, Rahul Sheoran, Sridevi Jade, T. S. Shrungeshwara, Maheswar Rupakheti

Research output: Contribution to journalArticlepeer-review

Abstract

We analyze long-term aerosol and precipitable water vapour (PWV) properties at two high-altitude sites (Nainital and Hanle) over the central Himalayan and western Trans-Himalayan region from 2008 to 2018. First-time assessment of the seasonality and variation in combined aerosol and water vapour radiative effects are also attempted, aiming to investigate the atmospheric effect on solar radiation over the Himalayan range that is especially important for the regional climate. A synergy of ground-based measurements from sun photometers, GPS (Global Positioning Systems) observations, radiosondes, along with satellite and reanalysis data was used to examine inter-annual and seasonal variability of PWV and specific humidity over both sites. The PWV is highest in monsoon and much lower during the dry winter season with slightly higher values at Nainital compared to Hanle. This is due to the lower altitude (∼2 km amsl) of Nainital, which is also directly affected by the Indian summer monsoon, compared to the Trans-Himalayan region. The vertical profiles of PWV from satellite and reanalysis data reveal a great consistency on a seasonal basis. The PWV is considered as one of the main greenhouse gases that exhibits a positive radiative effect at the Top of the Atmosphere (TOA) in the order of about 10 W m−2 at Nainital and 7.4 W m−2 at Hanle. The atmospheric radiative effect due to water vapour is about 3–4 times higher compared to aerosols, resulting in atmospheric heating rates of 0.94 and 0.96 K Day−1 at Nainital and Hanle, respectively. The results highlight the importance of water vapour and aerosol radiative effects in the climate sensitive Himalayan range.

Original languageEnglish
Article number101303
JournalAtmospheric Pollution Research
Volume13
Issue number2
DOIs
Publication statusPublished - 2022 Feb

Keywords

  • Aerosols
  • Heating rate
  • Himalayan range
  • Precipitable water vapour
  • Radiative effect
  • Vertical profiles

ASJC Scopus subject areas

  • Waste Management and Disposal
  • Pollution
  • Atmospheric Science

Fingerprint

Dive into the research topics of 'Water vapour characteristics and radiative effects at high-altitude Himalayan sites'. Together they form a unique fingerprint.

Cite this