Evaluation of meteorological characteristics and the influence of the Southern Annular Mode at newly established Bharati Station, East Antarctica

Abstract

The Indian Antarctic program, a multi-disciplinary and multi-institutional program initiated in 1981 with the first expedition to Antarctica, has been instrumental in advancing our understanding of Antarctic meteorology and its global climate implications. This study focuses on the latest meteorological characteristics of newly established research base Bharati aiming to unravel the climate dynamics of Bharati station in East Antarctica. The meteorological data for the period December 2014 to December 2022 have been analysed in present study. We observed the highest maximum temperature of 9.9 °C on January 5, 2018, and the lowest minimum temperature of −40.3 °C on September 6, 2016. The monthly mean temperature exhibits pronounced seasonal variation, with a summer maximum of approximately 0 °C in December and January, and a winter minimum of about −19 °C from May to September. While the eight-year observations are not sufficient for studying long-term trends, we identify a slight increasing tendency in temperature at Bharati. In addition to temperature, we examined the characteristics of pressure, relative humidity, precipitation, wind, and blizzards. The analysis reveals a negative correlation between the Southern Annular Mode (SAM) and temperature and pressure at Bharati. Station experiences predominantly easterly and northeasterly winds. The upper air data were obtained using radiosonde and ozonesonde ascents, enhancing our understanding of the atmospheric conditions in the region. These results provide important knowledge about the weather in Bharati and how it relates to the Southern Annular Mode. Understanding this helps us comprehend how East Antarctica weather influences global climate patterns.