Abstract Details
| Name: Manish Chauhan Affiliation: Space Applications Centre, Indian Space Research Organisation, Ahmedabad Conference ID: ASI2025_528 Title : Long-term analysis of meteorological parameters over Indian astronomical sites Authors and Co-Authors : Manish Chauhan1, Vibhuti Bhushan Jha1, Munn Vinayak Shukla1, Mehul R. Pandya1 Abstract Type : Oral Abstract Category : Facilities, Technologies and Data science Abstract : The Earth’s atmosphere adversely affects most ground-based astronomical observations. Observations in the visible and the Infrared are affected by cloud cover and atmospheric turbulence which can lead to a degradation in the atmospheric seeing. In addition, ground based observations are severely impacted or influenced by atmospheric water vapour. Atmospheric water vapour is of particular importance in the sub-millimeter regime where even slight increase in water vapour can significantly decrease the atmospheric transmittance. This is of particular relevance for SAC-ISRO’s proposed submm/THz telescope at a high altitude site, Hanle, Ladakh. In this study, we analyse and discuss the long-term trends (1975 - 2023) and statistical analysis of these meteorological parameters using the ERA5 reanalysis dataset over 10 Indian astronomical observations sites. These sites cover diverse atmospheric and climatic conditions with varying background conditions. These trends are studied over different timescales (months and seasons). Over the historical period, we observe an increase in columnar water vapour and 2m air temperature over various observational sites in certain time periods. We also discuss the trends observed in cloud cover, 10 m wind speed and total columnar ozone. Additionally, we will present climate projections from the future climate scenarios over these sites. Studying these long-term trends and climate projections are of particular importance for site characterization of upcoming Indian astronomical observatories. |